Should I Go To The ER If It Is Bleeding Heavily As I Am Pregnant?

Known complications : SCH that absorbed ; arcuate uterus (small); Bladder infection that wont go away Last Tuesday I had anatomy scan at 18 weeks 3 days. Everything was fine I m having a boy. This Saturday I woke up with blood. decent amount of bright pink blood. Went to ER and birth center they did US and couldn t find where it was coming from the tech dude said everything looked fine. Fast forward to today, Tuesday. I started bleeding about 6 am. It started out red pink and just kept coming (not enough to fill a pad) I called OB at 8 and they had me come in. When I got there I peed in a cup (UTI test) and when I wiped the situation got worse. It was BRIGHT red blood and ALOT. I started crying immediately. They took me in room and did US baby is fine HB 158 movin and everything. Did spec she sadi I m bleeding she s not sure from what and if I soak a pad in an hr to go back in. The bleeding after the bright red subsided almost completely until a hf hr ago I used the bathroom and wiped and A LOT of dark brown blood came out with about a quarter sized blood clot. It was all dark brown. Should I go to ER or does brown blood mean old blood.