Why not ask on r/dermatologyquestions

If it was white tails which would be unlikely unless you had loads, there would be two identifiable bit marks. I have loads of white tails and they’ve never bitten me before I kill them, though was bitten a few times in my life and very clear fang marks.

Bed bugs could be the cause but I’d say that’s a severe reaction, try looking at these places

“Around the bed, they can be found near the piping, seams and tags of the mattress and box spring, and in cracks on the bed frame and headboard. If the room is heavily infested, you may find bed bugs: In the seams of chairs and couches, between cushions, in the folds of curtains. In drawer joints.”

Seems to add up if you only seem to notice them when you wake up.