Mucus Plug?

I know this is sooooo TMI but iv never witnessed my own mucus plug if that what it is I'm having right now so any ladies help me out, I'm 36 weeks with baby #3 and I went yesterday to the hospital for a cervix checkup I am 1cm dilated and slight contractions and today I had an ultrasound and baby is head down I can feel her really low and soon as I got home I went to pee and this came out when I wiped!! Should I be concern is labor going to kick in soon? Like I said never seen the mucus in any of my two past pregnancy until now