Question about mucus plug **no pictures**

I'm 35 weeks tomorrow and not sure if I'm having normal discharge or if I'm gradually losing my mucus plug and whether or not I should call the Doctor. Yesterday went to change my panty liner and there was thin yellow discharge on it which I assume is just pee. But today I went to change another liner and the discharge was thick/goopy and very very light brownish/tan/taupe, should I make a call? Thank you!