Ok i have had sometimes where i got hard but lost it with a ex girlfriend. And it was disappointing and embarrasing. I really think i was over anxious and thats sort of the reason. But that memory has stuck with me alot and now sometimes when im about to have sex i think to myself, dont go down,dont go down and well u know the rest. I really starting to think lack in self confidence is part of my problem, some with health too but mainly its in my mind.