35 weeks and 3 days starting to lose my plug

Cherie
Tonight I started losing some of my mucus plug.It was just clear jelly like snot.And I have been having bad back pain. I'm just worried because I am at high risk of preterm labor since my last 2 were born at 35 weeks.Has this happened to anyone? I did read that as long as there is no blood its OK.Should I still at least call my Dr??Help