Arrgghhh!!!! New mattresses...fumigation!!

Bed bugs...lice...eeeekkkkkk (I'm going to run away screaming, go and rock in a corner and cover my eyes now!)

We don't have pets so I don't think it would be fleas, I haven't seen any around. I have checked out DS's bed, all around the seams and everything, and can't see any thing, not even fluff, so thats why I was wondering if it is bed bugs, plus the bites aren't in the line formations that it's supposed to be like, they are kind of in patches, like there are 2-3 bites in one spot, but not in a line. I have also thought of bird lice, we have alot of little birds around and our washing line is sort of under a tree...I don't think we have any in the roof though, I can't hear anything in the roof....
We so can't afford new mattresses/pillows or fumigation right now, and likely not for a while. I will continue to clean his room (and the house) meticulously and vac every day or two in the hope to at least minimise it I guess (so not what I need being 35wks pg with back and pelvic issues!). Maybe I should bring DS into DH and my bed and I will sleep in the spare bed (yes, we have strange sleeping arrangements at the moment!)
UGH!! This is all soooo gross!!! I'm so not a dirty person and I know having these sorts of infestations isn't about being dirty, but my goodness it makes me feel so dirty and makes my skin crawl!!