There's no such thing as "normal" when it comes to sex, particularly when it comes to male endurance. One guy might be able to last for a long time, and another may only last a short time. But both men are perfectly healthy sexually.
So the focus here shouldn't be "is he normal or isn't he?" but "are we compatible or aren't we?" Regardless of what his excuse is, if you're not happy with what's happening in the bedroom, then you have every right to want to change things. It doesn't matter if he's your first. You know what you like and what you don't.
You do need to bring this up with him, because the situation as it stands now really can't continue. The key is talking about it without hurting his feelings. I suggest bringing it up as a project that you can both work on. Pitch it as a team effort. Not that I want to put words in your mouth, but perhaps some of these phrases may tumble out:
-What can we do to have more fun?
-Is there anything you want me to do?
-There's no pressure, just be yourself and relax and don't worry about it.
Just be honest with him, be kind and be patient. Some guys do get better with time, as they figure out how their body works when it is in contact with someone else's. Expect him to work at it, but don't expect it to take forever. If it's months from now and he's still not able to give you what you want, then you might want to consider moving on.