I do have ED and the orals are extremely over-rated. Most guys think that they are going to drop a pill of some sort and then get this monster erection that will take them to ejaculatory nirvana.
Yes, in reality, you can chemically create the nirvana your imagination is trying to conceive, but, it is not first not simple, second not cheap, and third probably not easily legal where you are, and most importantly it would not be possible with one thing it would take two and none are Viagra. That does not mean it is not possible, it just means that it is the four things that have already been said. It is also not possible with Viagra which is Sildenafil Citrate in oral form.
Fantasy stories imply that the blue pill will do a number of things.
This drug along with the other orals are what are called PE-5 inhibitors and these drugs are not capable of doing anything in reality without your mind as a full accomplice. What you might notice was that it took "less stimulation" to get you going and that your erection time might be somewhat shorter. In truth, a case of the "extremely horny's" would probably still in reality be better.
The next thing is that the orals do nothing to the natural control responses. Both males and females produce a hormone called prolactin. In the female, it induces lactation and kills the sex drive of that female during breast feeding. Males use it as a control hormone. As your body and brain move towards ejaculation/orgasm, your body is producing a bolus of prolactin which is dumped into your bloodstream to temporarily kill the erection and the desire for sex as you ejaculate. The quantity of this increases with age and that is the reason that "recovery" takes longer. In so many words, you lose the desire even if only for a period of a few minutes.
There is a medication out there that will arrest this process in a number of men and as a result you do not lose the erection and you do not suffer the post orgasmic sensations that take place in the penis marked maybe by excess sensitivity right after sexual intercourse. You can go right on humping away and head for ejaculation number two if it works for you.
Where Viagra can shine, is that as you hump away, it, in a percentage of men, also plays a little trick on the neurological pathways and can slow or delay ejaculation. As the stimulation level increases, so does the strength of the erection because the PE-5 inhibitors are working to keep the erection going, and, the more you stimulate it in a man with little nor no erection problems, the harder it is going to get. This is where a part of the "fantasy" of this stuff comes from. The problem is that this backfires on a percentage of users. I have known men in your position who have tried this, and, what they experience is an incredible sexual experience that becomes torture when they get to the edge again and again and are not able to achieve ejaculation. Does it work, yes!, but it does have it's downsides to be certain.
In my own case, I have an Rx for Quadmix, which is an injectable I use for my ED. I give myself an intracavernosal injection, and then within about 5 minutes, depending on the dosage, I have a throbbing monumental erection. One of the problems with ED, and one of the reasons that you don't want to risk it, is that if you start to lose erection firmness the first thing you lose is not the ability to penetrate, what you lose is sensation.
If you are going to want to try an oral, I would NOT endorse Viagra. Viagra is a drug that has few benefits outside of a few very unusual medical conditions. If you are going to try something that is far less dangerous, then my personal opinion, and I am NOT an MD, would be Tadalafil which is by trade name known as Cialis. It lasts up to 36 hours and it has other benefits to your body in that it also causes a minute dialation of cirulatory vessles benefitting the heart liver and kidneys. It has had a far better track record and is the only one that some MD's will even prescribe at full strength on a daily basis, if one has other things going on that could impact circulation. There are MD's that pop Cialis themselves like candy because it does not have the quantity of dangers that Viagra does.
The main problem with all the orals is that they act from a systemic base. This means that you take a pill and the drug in that pill has to be strong enough to not only get to the areas at the base of the penis, but it must also penetrate the blood brain barrier, it must go into the liver, the kidneys, the spleen and everywhere else.
When I take an injection of Quadmix that injection goes into the corpora cavernosa of the penis and acts only on the structures required for erection. Very little of the drug combination by percentage goes to other locations. Remember that in an oral you are getting Mg or milligrams. In my injectable I can get a 100% erection on only about .020mcg of the most potent ingredient which is Alprostadil. We are talking micrograms instead of milligrams.
Now, before you ask the questions, you can't get this over the internet at all because it has to be custom made by a compounding pharmacy. it is not something to "play" with and can cause major medical problems if you make an error even once. Can it create nirvana, yes, but my friend I would happily trade my "injectable nirvana" for your works perfectly every time set-up.
Though people play with the orals every day, and they are safer than originally thought, it is something that is really not magic. In the U.S., most MD's have samples of this stuff that they give out for free. In the UK there may be samples as well. Go in to the MD, tell him that you've been having a little trouble lately and ask if he has some samples to get you past a "stressful" time in your life with your gf. Unless the UK is absolutely sample free, (which I doubt) he will probably had you a trial pack of Cialis, and you can have your experience and see if it really is worth it. Also this way your MD knows that you've at least tried it and you've done it legally that way.
Having been down this road myself, I don't think that you are going to find that it does all that much for you.
Best of Luck