mucus plug?

I'm 33+4 pregnant and I put a pad on and I checked it and it was pad was full of yellow discharge from the back to the front is that my mucus plug I'm getting a lot of pressure down below and on my tail bone this is my second pregnancy I went early with my first at 37+3 I was at the doctors last week and she said I'd go early with this little one I'm just worried il go real soon like real sooner than I expect