Labor getting closer?

37+5 today. I have had sciatic nerve pain this pregnancy but not horribly and just in my butt cheeks. Well.... today is a different story. I literally had the pain shoot down my leg to a point where I just couldn’t walk anymore. I also have been having the sharp stabby feeling down there WAY more than usual. Midwife doesn’t check for anything until 39 weeks so I have no idea if I’m effaced or dilated. I have been loosing the tiniest pieces of my plug for a week or so now, just about every time I pee there is a little yellow blob but today there was slightly more and even a tinge or blood.