Mucus plug?? Help please

Okay, I’m 35 weeks pregnant & all of a sudden I went to wipe and I had an extreme amount of discharge. Next time I used the restroom, same thing. My sister said it could be my mucus plug? I usually never have discharge. Well, I looked it up online and it says call your doctor if you think you’ve lost your mucus plug before 38 weeks, should I?

This is my first pregnancy. Everything is brand new. I go to the doctor next Tuesday, so should I just wait unless I have any signs of labor?