Light bleeding?? 😭

Randi

I've been bleeding off and on all day. I'll be 28 weeks in a few days. I had an u/s yesterday (before any bleeding started) and everything looked great including my cervix. Baby is as active as always today and is very healthy. I haven't had recent intercourse, heavy exercise, or a pelvic exam. I do have a few small placental lakes but idk if that could cause bleeding. No contractions (other than the normal occasional BH) and no cramping, the only pain is just some light ligament pain and rib pain because baby likes my ribs lol. The bleeding isn't nearly heavy enough to soak a pad though I have been wearing pads to keep my underwear clean as it's more than light spotting. It's reddish brown but more brown than red, almost entirely brown when I wipe. No bright red at all. I called my doctor and she said to take it easy for a while and go in if it gets worse. I'm just super worried, I know bleeding at this stage is not normal.... Can someone tell me any reason why bleeding might happen at this point??? My doctor told me at my 20 week u/s that I had a small subchorionic hemorrhage, could it be the hemorrhage finally bleeding out?