Stomach tightening (feels like contractions) at only 11 weeks ??

I have preterm labor issues because my body tries to go into labor early .. My son was born at 32 weeks and twins born at 29 and the only way I can describe these feelings is they are similar to what I felt like when I would have contractions at 5 1/2 months .. But I'm only 11 weeks so what do you think ? I am considered high risk and have to get ultrasounds a lot to check my cervical length . Do you think my cervical length is starting to shorten already ?