What Was The Slimmy Greenish Discharge After Using The Washroom?

Im going on 37 weeks and Last night i went to the bathroom and when i whiped i had a heavy discharge of slimmy greenish almost looked like snot.. And a couple times after that when i whip i still have alittle come out but not as bad.. Im having alot of back pain as well with this what does this mean.. My obgyn checked me last week and said that i would go early but I was still closed just very thined out. and the babys head was really low..