I am a 16 year old boy and me and my girlfriend want to have sex.  However both times we have tried I lose my erection just before I put the condom on.  I can get and sustain an erection easily when masturbating and during foreplay but I just seem to lose it.  How can I solve this problem ? I do want to have sex with my girlfriend and I feel like I am ready.  Do I lose my erection because of nerves or because of an erectile dysfunction ? Thank you.
Hello, Yes this could be due to stress, anxiety or low self-esteem. You can overcome these conditions by doing meditation, get some education about sex and sexual behaviors, sex therapy to have better performance and counselling sessions to manage stress and anxiety if any.  Since you are having normal erections, this is not due to any organic cause. Hope I have answered your query. Let me know if I can assist you further.