It can mean a few different things.
1. It can just mean he is inexperienced, and you had him so turned on that he couldn't help himself. Guys have to work at lasting longer. So guys with less sexual experience won't last as long as guys with a lot of experience. But.he will probably recover quickly, and last longer the second time around, so don't get discouraged.the night need not be over.
2. He may have "problems". Some guys need medicines to help them "last longer".
3. He may be a punk, and just be in it for him. The best way to tell if this is the case is to see if he was apologetic and embarrassed afterward. If he just hopped off and smiled and said "Thanks.that was great!" Then he is a piece of dirt, and you should kick him to the curb, because he could care less whether or not you enjoyed it.
4. You the Girl. You overstimulated that boy so much that by the time you glided him inside you, that tight grip of yours was just too much for him to handle. Don't get mad at him for you being too hot too handle. OUCH baby!