so i have been having some problems lately. by the way, i am 21. here they are: -low sex drive -inability to get fully erect for intercourse about 35-40% of the time -inability to stay erect -inability to get erect on my own (as in, i usually need to look at porn or something to get hard - self-stimulation doesn't work) -long recovery time - at least a day before i can ejaculate again -small total ejaculate i haven't had these problems (except for long recovery time and small ejaculate) until about a year ago. now i am very concerned. i saw my doctor and he gave me some cialis, which is fine for now, but i am worried about the long run - i am far too young for this, in my opinion. i don't think it is all in my head, because it seemed to come out of nowhere. in a few months i am having my testosterone levels tested, but i was wondering if any of you have any ideas/suggestions. i should also mention that i have been taking 3G of l-arginine per day. thanks in advance for any insight.