Red bumps on butt cheeks

[Asjasa]

I've been staying with my brother who I recently found out has bed bugs, I have noticed I am getting bite like bumps on my butt cheeks they are hard but have no fluid or white heads small and only have one spot that has five or six then the other cheek one big one and small one. high button cheeks in crease, have a huge butt, could it be bites, swear bumps? I donto feel comfortable going to a doctor. Have been std checked with last sexual intercourse. All came back negative,  any suggestions?

[Sandman2]

Really sounds like bed bugs.  google it and you can see pics of bites, etc. and how to treat and get rid of.