Is this mucus plug or something else?

So I’ve been in and out of the labor and delivery with high heart rate.. I’ll be 38 weeks on Monday. That’s besides the point I’ve been losing my mucus plug now for a couple of days. But tonight I have noticed when I wipe after peeling it’s a brown/pink color with the mucus. Is that from the mucus plug? Or would it be something else? I know it isn’t uti because I was tested for that last night. I know I’ve been having contractions it’s been documented with my nsts and being in the hospital. But I’m just curious