yep. I know exactly what they are. they are carpet bugs. No they dont live in your carpet. They are a larva from a bettle that tends to live in areas like attics becuase they find old birds nests and the like. The beetle lives and lays its eggs in the old nest (usually found in attics) and the the grubs find their way down into the house through small eiling cracks, down your walls and sometimes only your carpet, which they will happily eat but you wouldn't know they were there. you wont see huge chunks missing :-) although they are unpleasant and unsightly they are harmless. They can also be encouraged in damp areas. If you have a lot, which it looks like you have there, you could get in touch with your local environmental health and ask them to deal with the problem. If you rent then it is the responsibility of the landlord to sort out, though not all landlords are so accommodating. When I had then I would maybe find twenty over a month period. It was then i called out the Environment health. I hope you dont have too many. I just used to pick them off the walls with some toilet roll and flysh them down the loo. Though to be honest, the landlord did nothing and I moved out shortly afterwwards (not for this reason though). Hope this helps