10 weeks pregnant and still getting normal period.

I thought I was having a miscarriage but my doctor said the baby is perfectly fine. I went to the doctor yesterday because I started bleeding 6 days after my other period ended. Yes i have been getting my period they arent super heavy but it’s still bright red blood and I do wear a pad but I only switch it out 3 times a day. The doctor doesn’t know why but the baby is healthy. I never thought I would be one of the ladies that gets their period during pregnancy but I am and it’s weird and kinda scary.