Help IDing tiny caterpillars in my house

For the past two months I've been getting red bumps, and there's always a few weeks between them... And it always happens when I'm asleep. At first I thought I had bedbugs. But there has been no other evidence of bedbugs, and my roommate has never had any problems. In trying to give my room a really thorough cleaning I found these little worm-like things on the baseboards - four of them in total, and something that looked like a shell of one (except I know caterpillars don't shed shells). But they have a bunch of tiny legs, and they are a reddish-brown on top with a clear belly. I also found a larger caterpillar-looking thing, mostly pale/grayish, about 1cm long.

Do these sound like carpet beetle larvae? I haven't seen any adults and we are all hardwood, but I've heard they live in clothes or mattress too...

Does anyone have any ideas? I live in the Pacific North West if it makes a difference.