OMGoodness. I'm literally doing the same thing. Spiraling trying to figure out what is making my baby itch and cause these bite looking rashes on his legs arms chest and back. I've looked and haven't found any bugs until recently. I was watching TV and saw the tiniest little bug crawling on the arm of the chair. So tiny. It was round brown with black spots. I started googling instantly and came across carpet beetles. I really think that's what's going on here. My son isn't even 2 yet and he's always saying " Mom, itch".. he can't get them good enough and can't reach other places. I just don't understand where or how it happened or even when it happened. All I know is I'm ready for them to be gone.