How mush sperm is enough?

My husband and I hadn’t had sex for 5 days and when we finally did, he hardly had any sperm.  Is this normal for a guy not to have a lot of sperm after that long of no sex?  He is very honest, I jokingly asked him if he had masturbated in the past 5 days and he said no.  I know he would have said yes if he had.  Am I being paranoid or sometimes is it just a little bit that comes out?

[jml1986]

There is no right amount. It varies from man to man.

[DIBOS]

I don't know how much it variues from man to man, but as a man, I can tell you the volume of the semen that I ejaculate varies from orgasm to orgasm, even if it's been a few days since I've come last. Sometimes getting distracted during orgasm causes the ejaculation to shut down, so there's less. Did he pull his penis out of you before he came? If so, there could have been enough of a distraction to make him shoot less.