I'm 26 years old. When I had sex with my girlfriend for the first time I had a normal climax and everything went perfectly. But after this first sex i'm not able to maintain erection and enjoy sex at least for next two days. The issue with the 2nd and 3rd intercourse within one day is the sperm not ejaculating out side and some times the erection suddenly goes off. It's very embarrassing for me to go off suddenly. As we are new couple we wanted to enjoy more sex frequently. Please help me with my issue guys.