Im 24 years old, I haven't had successful penetration yet, so basically Im a virgin. Im in a 5 months relationship. I tried having sex with my girlfriend but, although Im horny as a hog before sex, when Im about to penetrate my mind goes off and penis shrinks gradually. Im aware this is mainly head problem. i was wondering if viagra or cialis would help to override that neurosis and maintain erection? p.s. I cannot describe how this problem affects my joy of life. I feel deprived to the maximum.