Breakthrough bleeding

Hey all! Has anyone experienced breakthrough bleeding early in pregnancy?

I got my bfp yesterday (technically AF due on Sunday in 3 days) and started period type bleeding today. I called my obgyn who won't see me yet because I'm so early, said if it gets heavy & painful to go to the ER. It's not that heavy or painful... definitely like a period. I am already aware it might be a chemical pregnancy & am going to get blood work done to see what's going on but wanted to see if anyone had other stories. I took another FRER hours after the bleeding started & it was even darker than the other ones, not sure if that's relevant at all.

Also just wanna say this is a beautiful community filled with support, and makes all of this much less intimidating.

Thanks