Gross/tmi/embarrassing water broken? White grains/flakes?

Hi, 
I'm 37 weeks. I had a lovely long bath today and as a got up to get out there was a gush of fluid. It could have been my waters? Could have been urine? 
So I then put a finger inside (tmi sorry) and it had loads of white grains and flakes on it, checked again and same thing. This is not normal for me. 
I also lost mucus plug this morning. 
I've now put a pad in to monitor but I've had a very leaky bladder due to pressure anyway so not sure I'll be able to tell from this method. 
Any thoughts or experience of this??!!