I think for me it depends on the motivation and, oddly, what's going on in my life at the time.
I tend to find early on in a relationship I can go a lot more frequently and including several in a row (time to at least catch my breath after each time is usually preferred), but I don't think I've had issues going more than once, I guess it's just where the mood takes you both, sometimes that one time can be so good that it's more than enough.
But if you do want to keep going, I'd suggest what seems to have already been said, take your time and just have some more foreplay, touch each other, kiss/lick, etc. If he gets a second wind, great, if not, at least you both get some extra fun
Also, I found when I was working long hours with it really drained my energy and lost must of my motivation for sex. Perhaps something to avoid.