I think it is TOTALLY fucked up how everyone has busted this young mans balls like this. He put a very personal problem he had up for everyone to view (which took bigger balls than most of you will ever have) in the hopes that someone might ease his mind and all you pricks are doing is making it worse! I am all for making light of any situation and I try to find humor in even the most serious of circumstances, but i dont think that is what he was looking for here... He certainly wasnt looking to be called "gay".... We all have our problems and we all need some help and support sometimes, but it takes a "real" man to come forth with this kind of shit and admit it.
Anyways bro, dont sweat it, you are fine... That shit happens from bad nerves and the more you think about it the worse it could get, so just forget about! And like someone was saying, just go jerk off and if it works then, you will know that it was all in your head. And I seriously doubt at 18 that you need any kind of help with your Test....