So I’m 11 weeks PP.

I went on the birth control pill for a few days, and then had to take a break because I had to take an antibiotic for bacterial vaginosis, so I got my period. It ended on Dec 18th and I got my period again today, less than two weeks later. It’s very weird though, kind of a darker red and very light. No cramping at all which is super rare for me. I’ve always been VERY regular also. Can someone please tell me what might be going on here?????!!!