I discovered a small rashlike area on the underside of my , it looks like a hickey.?

It doesn't look like Inflammatory Cancer, according to everything I've seen. It's strange! It consists of several purplish-red pinhead dots in a circular pattern. I have an appt with my OB next week for my 28th week checkup (Pregnant), but wanted to see if anyone has had anything like this in the meantime.