I function on about 6 hours of sleep on weeknights, but I have to play catch up every few weeks on the weekend. DD is a pretty reliable sleeper, and I'm a good sleeper, so her night nursing doesn't really disrupt our resting very much. But even so, if I don't get extra rest on the weekends I crash and either get sick or absurdly emotional and angry.
good grief, I just noticed your sig and that your babe is just a couple months old. (edit: ok -- i think I was looking at someone else's sig. But even so.)
Of course you need extra sleep. You've been recovering from birth, you're dealing with the constant physical and mental demands of a newborn (edit: or a not-newborn), and you're most likely trying to maintain a semblance of a normal life including obtaining food, staying clean, etc.. OF COURSE YOU NEED A LOT OF SLEEP.
Is the question one of "you're sleeping so much, are you sure you're healthy?" or more like "you're sleeping too much, you lazy butt!" ? If he's worried that all your sleeping is a sign of depression, well, ok, it's good of him to be concerned. Otherwise... back off, buddy - you really don't want to go there.