What Causes Back Pain, White Vaginal Discharge And Discomfort During Pregnancy?

I m 32 weeks & 6 days pregnant and I ve been wondering if I m showing signs of pre term labor this is my first time pregnancy and I m at risk of preterm labor but my ob gyn has not checked to see if I dilated she said she s not checking until I m 39 weeks. I ve seem to have lost weight , I have loose bowel movements , my groin hurts everyday and all day , I use the bathroom more frequently again, I have morning sickness again, my whole stomach gets tight for a couple minutes every hour for the past 3 days, the baby seems to be kicking less and less each day as well and it feels like she has dropped , I ve been having lower back pain & white discharge . am I having pre term labor symptoms and if so what should i do ?