Pimples on my butt

Sorry for the exposing photos but they are needed here. I’m male, 21 years old and the last days I noticed while showering that my but cheeks have some pimples that are more than usual, I’m used to acne but these had no goo on them so I thought it wasn’t that. Now the thing is that I guessed it could be from shaving with a trimming machine that bursted my skin but I shaved around 2 weeks ago and this only abrupted now. Can anyone help me?

I’m sorry for my english, it’s not my first language