Missed ectopic or miscarriage

I should’ve been roughly 4 weeks when I started having pain and bleeding. it seemed mostly one sided so I had blood work and both a regular and transvaginal sonogram done. Dr. Said everything looks normal, no fetus in tubes or uterus. Thinks I am having an early miscarriage.

Is it possible at 4 weeks for them to have missed an ectopic on the scan? Would it be hurting already? Or are miscarriages just this painful?

Experience? How long did you bleed and feel pain for? Thanks.