Ivermectin is NOT effective for COVID, that was disproven very early on, after several people poisoned themselves with it. It is a drug, it isn't harmless, don't take it on a whim.
Anyway, bird mites cannot feed off of mammalian blood. If you have cleaned the room and washed the sheets, it is unlikely to be that.
It is more likely to be an allergic reaction. What have you sprayed/cleaned with? Did you use a different detergent to get rid of the mites? Did you put something on your bed? It may even be an allergic reaction to bird dander - which goes through the air as dust, settles on your clothes/bedding and then is pressed against your skin for hours.
Before you start dousing your room (or, heaven forbid, yourself!) with more chemicals, if you have a sudden rash, see a doctor, don't ask the internet. Even if it's hard.
It also may be fleas. Which, I get it. I have over a dozen cats and 3 big dogs, fleas happen. Especially down south.
TSC has a generic capstar. I'll pull up the link. Get the large dog size and dissolve the pill in 5cc of water, then 1cc will treat a cat. Do EVERY animal in your house on the same day. That will kill every flea that bites them for the next 3 days.
Then, get some mothballs and put them in your vacuum cleaner bag (or canister) and vacuum everything, floor, couch, mattress, everything. Hang all your bedding and the pet's bedding outside - yes, especially if it's freezing. Exposure is one of the few things that kills flea eggs.
If you feel that isn't enough, then Ortho has a flea and bedbug spray, it's about 16 at Home Depot, and you can order it off their website (but really please do make sure you're not reacting to any chemicals now!!! I just had a nightmarish reaction to a new brand of powdered bleach. In my laundry = no escape) and treat the house with that.
And, because nothing but exposure to the elements kills eggs or pupae, do it again in 2 weeks once everything hatches.
I have to go through the rigamarole at least once a year, because fleas happen. An outbreak usually costs me around $50 to get under control.
https://www.tractorsupply.com/tsc/p...ea-treatment-for-dogs-over-25-lb-711650130006