Help!

Chelsea
Not sure if I lost my mucus plug but don't know what else it could be!
I was wearing my night gown and sat on my bed, and got up to pack some things and noticed the back of my night gown had this snot like clump on it directly in the back like where when I sit down my vagina would be!
Mucus plug? Idk what else it could be or how it could get back there..
I'm 37 weeks