Preterm Labour - Previous experience

Hello! With my last pregnancy I went into preterm labour at 24 weeks. Baby had chromosomes problems and wasn't expected to survive anyway and Doctors seem to think I went into preterm labour as a result of my baby being incompatible with life.

However - I can't get it out of my head that it could happen again, even though my current baby is healthy. I have occassional pink discharge (started after 11 weeks - now almost 14) and just have this bad feeling that my cervix is weak. Im going to bring it up at my next appointment on Tuesday.

Has anyone dealt with preterm birth before or is high risk for it now? What signs should I be looking for? What can they do to check me? Is there any precautions I should be taking?

Thanks for any advice!!!