Spotting for 36 hours at 27 weeks

Hello, I have been spotting for over 36 hours now. My husband and I started to have sex Wednesday evening but stopped due to bright red bleeding. I called the Dr on call who said if there weren't any contractions or hemorrhaging it should be fine. It has been over 36 hours now and I am still spotting, it went to a light pink back to bright red. No additional intercourse and I haven't done anything beyond housework. Baby is moving around, I have been having slight lower back pain, a little bit of lower stomach pain, and now pinching in my cervix. I called again and am waiting on a call back but don't feel exactly comfortable with their responses. I haven't had a good pregnancy so far and haven't gained any weight either. Just looking to see if anyone else has experienced this type of situation and the outcome.