The hip/back/lower abdo pain sounds like it could be SPD, maybe google and see if it sounds like it, is it worse turning over in bed and separating ur legs like putting pants on or getting into a car? The nausea etc, is your blood pressure ok? Do you have swelling or anything? If you don't think it's the start of labour I'd go to the hospital/GP tomorrow. Just to be safe and for peace of mind.