Chemical Pregnancy?

AF arrived yesterday, right on schedule. I was SURE it was my month but I took test after test with BFNs. Can anyone tell me is it possible to have a chemical pregnancy without getting a positive test? And also with it started same day as AF? I have never in my life had so much pain or blood. I’m bleeding through tampons immediately and couldn’t sleep for the pain (even taking pamprin). I’m just wondering if I need to contact my doctor, so someone please give me some insight. Thanks!