The pain you are experiencing is because they literally cut out a ton of veins and tied off the vein causing the trouble. I had pain from my nuts all the way to my navel because the vein is located on the spermatic cord that winds up and around your bladder. The nerves will literally be in shock for a while and the pain will subside only gradually and will most liekly re-occur. Although you will be able to have sex, you will probably feel a "pulling" during ejaculation, that, the first few times, may be painful and you may have residual pain so that you may not want to have sex. The good news is that it all heals in time.
If they implicitly to leave the tape on, then leave it on. If they told you to keep it clean, the only way to do that is to take off the tape in the shower but you best have a replacement for it after you clean and dry it so you can put another one on. I had disolvable sutures covered with gause and a tiny, extremely tight jock strap with only a hole for my penis but my incision was directly on my left nut. It took me a good 6 months to completely heal to the point where I no longer had to watch where I stepped because any jarring caused an instant kick in the nuts pain. Mine has come back and needs to be done again. I will do an embolization this time.
Make sure you eat if you are taking those nasty pain meds or you will get sick.