4 week old kitten wont eliminate, has swollen stomach and butt

my poor kitten! i rescued him from starving to death but his stomach was really huge. he also had an upper respiratory infection and seemed really hungry, but didn't want to eat much. we found out he probably had roundworms so we got some medicine for that and he's also on medicine for the cold. he's got a much better appetite after the roundworm meds, but as far as i know he hasn't peed or pooped at all. his stomach is still rather swollen and his little butt is swollen too, like he really has to go. i've tried rubbing it with a warm cotton ball and all it seems to do for him is make him squirm away from me. do i need to do this constantly until i get something out of him? i really don't want to hurt him, but i'm scared about how long he can go without passing anything. help!

You know, I want to answer your question, and I really do want to help. I actually have done volunteer work with some NYC cat rescue groups and cat sitting for rescued cats, done a lot of medicating animals and such like. I do know and can tell you that after a kitten this age eats, his midsection swells, because his body mass is so slight. The meal shows. The thing that baffles me is this thing about a "swollen butt". That's a new one. I've never seen it, and I can't imagine it. But tell me: when you are constipated, does your behind swell? I certainly hope not. So this one just baffles me.

By the time a kitten is four weeks old, it eliminates without stimulus from the mother's tongue, so the cotton ball-warm cloth maneuver won't help, and if he is squirming away from you, he is telling you just that.