he doesn't know what he's doing and neither do I

C
So I had sex with this really hot guy but it was very obvious that he hadn't been with too many girls if any. He went for maybe 30-45 seconds and as soon as he came he stopped. I've never slept with anyone that's been inexperienced so I'm not sure if he really knows what to do, because I don't even know what to do!! Help me?!?