Did I lose my mucous plug?

I am 38w4d and yesterday I went to the bathroom and when I wiped I had some icky slime on the paper. It looked like I just took the toilet paper and scooped out a hunk of petroleum jelly. This is my first pregnancy, so I have lots of questions. It was not blood colored or anything. Was this my mucous plug? Does that mean labor will be starting soon? Also, does losing your plug help you dilate more?