37w + 4d blood string after using the bathroom (TMI)?

Hello, sorry for the picture (TMI) while I was using the restroom I noticed a tiny string of blood ( the foam is soap). I have been feeling a lot of pressure down there today and a lot of Braxton Hicks. Could this be an early sign of labor? My appointment is tomorrow. It is almost midnight not sure if I should call the nurse on call or just wait till tomorrow.