Small Red Bump In The Center Of My Butt Cheek. Could It Be An Infection ?

Female, 42, 5 6 and weigh 145 ( lactose intolerent and possible gluten issues) ...Sorry this question is a bit long...A couple days ago I felt a small painful red bump, the size of a mosquito bite , in the middle of my butt cheek. My first thought...I was bitten by an insect but then a small white pus bump formed right in the center of it, so I held it tight until it popped and now I have a mark (ugh)... Here s where I am now a bit worried, last night a discovered another small painful bump, but this time its almost under my butt cheek and looks as if a small white bump will occur on it as well... I don t know why this is happening and the only thing I can think or possibly tie the now 2nd bump to is this... last week, on July 4th I was over a male friends house to hangout and later that evening we did engage in some sexual foreplay (body rubbing), a lot of touching but no penetration...I also used his bathroom (just trying to include as much info as possible) Also, I am not ashamed to admit if any penetration occured, so what I am stating here are true facts. I am not experiencing any pain or discomfort/bumps or anything in my vagina area or any other discomfort besided the small bump which I again have never experienced before (never had pimples/ acne in any area on my body except my face ) The other thing I noticed/experienced, a couple days ago I felt a little quizzy, had chills and stomach bloating but no cramps and serious pain, just felt weird and thought I was a bit warm, but my temp was 98.4 and I tied it to some baby bella mushrooms I put in my omlet. After researching food/mushroom allergies I thought the mushrooms casued me to feel ill because for two days saturday and sunday I put the mushrooms in my omlet and shortly after my stomach began to bother me and I felt weird, same as sunday, but noticed chill s. So Monday, no omlet and was not feeling sick at all, until this second bump appeared last night...and the only discomfort today is it hurts if I bump that area or touch it... I AM LOST and very concerned...I know about STD s and I am careful, but I am thinking I Could I have an infection from playing around with my male friend??? or maybe using his toliet? Although He s clean, kinda a neat freak like myself, and also has a dog who was in and out the house most of that day... I am trying to put as much information here possible to help get the best answers....HELP PLEASE?