Ladies I have a question is it common to bleed during pregnancy? I bled really badly in the…

Ladies I have a question is it common to bleed during pregnancy? I bled really badly in the beginning in relation to a placenta abruption. I haven't bled since I was about 10 weeks. I am now 22 weeks and just noticed blood. I have contacted my doctor and I am waiting for them to call back. Should I stick to the safe side and go ahead and go to the ER?