Mucus plug (no pic)

So I'm 36+6 weeks and I was feeding my animals and I felt like I was wet so I went to the bathroom and on my panty liner was a battery size glob of thick snotty looking discharge. I've had discharge my whole pregnancy usually thin and clear but not at all like this and so I wiped and there was more mixed in with my normal discharge. Luckily I have a doctors appointment today..