Am I having an ectopic pregnancy?

I had what I thought was a period on February 26th - March 2nd. Normal bleeding like a period. It stopped. Then I started birth control on February 28th. But stopped that on Thursday March 11th. I started lightly bleeding and it’s dark brown (I assume from starting and stopping the BC). I took a pregnancy test yesterday (March 15th) and it came back positive. I’ve had very mild cramps in my pelvic region but that’s about it. What would an ectopic pregnancy feel like? I have no idea how far along I am.