the inability to achieve or maintain an erection could be medical or psychological or both. unfortunately it would not be possible to determine a specific cause in your case based solely on the limited information you have posted in your question. my first inclination (no pun intended) would be to feel that his is a limited psychological response perhaps due to some performance anxiety. if you can achieve an erection at other times such as a morning erection or during masturbation this would be the likely underlying cause. nearly every man at one time or another will experience temporary erectile dysfunction. alcohol use can be a factor so you may want to consider giving it up for a while until things improve. you did not mention using other recreational drugs but cannabis ecstasy and others have been implicated in temporary erectile dysfunction. if not you will need to seek the services of a skilled medical professional to look for a medical explanation.
i don't know what is wrong with me but im 20 years old and i recently stopped being able to have erections. i am in a fraternity and i drink very often. i also use tobacco. i just recently got together with a girl and i have not been able to have erections since the first time we had sex. the first time i was able to have a full erection and sustain it. it has been almost three days and i have not been able to have an erection.