Sorry you are going through this.

Bad abdominal pains can be caused by any number of reasons and should not be taken lightly. I am a bit surprised the ER didn't run any tests other than a pregnancy test if you are having abdominal pain?!
Do you have a family doctor you can go speak to that can refer you to a specialist or at least to a better ER? I would be wanting a 2nd opinion on the pain.
As far as pregnancy symptoms, which symptoms are you having?