very very light periods

Ok so my question is very stupid because I'm so sure I know the answer. but is there any way that you can be pregnant and still have your period? I ask because I missed a period (Nov) then the next month (Dec) I got on But it was only for a day and was light (very unusual for me normally period is between 3-4 days) then the next month (Jan) I wake up go pee and when I wiped I had a little blood on tp so I put on a linner. the next bathroom trip I had nothing in the liner but still a little blood on tp but by my third trip there was no blood on the liner or on the tissue paper. & that was it. I feel really stupid for asking... lol