I had a brown flat spot just appear on the head of the penis a couple months ago and now a couple more popped up on the foreskin (im uncircumsised)?

A couple things: These can be a type of mole called melanotic macules or early skin growths of seborrheic keratoses. These are completely benign & tend to happen more in some people versus others. There is a small possibility that these could be early flat warts. Seborrheic keratoses & warts would become more raised over time. I would recommend an evaluation by a dermatologist to make sure they aren't warts.