Signs of preterm labor approaching??

I’m 30 weeks i was diagnosed with a short cervix I’ve been having a lot of mild lower back pain and contractions for the last week and every time I use the restroom I have bits of my mucus plug coming out plus a TON of discharge is this a sign that I could be going into labor soon or that I’m dilated any?? I’ve read that those were all signs of preterm labor approaching.