What is this on my babies head???

Hi I’m a ftm and I don’t know if I’m over reacting but I’ve seen this little bald spot on my sons head for the past two weeks so I know it’s not a moskito bite, it also doesn’t seem to bother him or itch. It’s on top of his head, it’s not the same as the bald spot they get in the back because they lay down a lot. Anyone seen anything like it or know what it could be? I’m worried I’m gonna make anappointment his pediatrician first thing tomorrow, maybe you can’t tell but there’s really small red bumps on his scalp