Chances of pregnancy?

So I am 2 days late on my period and 2 weeks prior to my period due date I felt some mild cramping on my lower back and lower abdomen. Nothing major. I figured it was pre period cramps. So now I’m 3 days late. I don’t have any symptoms of pregnancy. And I am on birth control pills. I take them everyday haven’t missed a does other then like 1 week ago that I took it a couple hours late. But I haven’t missed a day of the pill. Is there a chance I could be pregnant? Or am I just freaking myself out?