This is a simple situation. The main thing is that you need to know to control your orgasm and you also have to understand the ways of enjoying sex.Since you mentioned that this was not the first sex you had then it must be certainly the complexity of having sex with the girl you were longing to have and when you finally got it you blew it up. I know a good material that can help you to improve sexual life . Just try it and you will thank me later. Enjoy!!!