I get excessive cm during pregnancy, and it ranges in colour from green to clear. I find after I do a #2 its really heavy, and it comes away in big strings. Sorry if TMI.
You will know your plug when you lose it - specially in the last week of pregnancy! Its not stringy, it looks like a massive hoick or oyster, its completely revolting!
I presume you have talked to your Dr/OB regarding the pinkish discharge? As long as it stays clear/yellow, and doesn't smell, I'd just mention it at your next appt.