Cervix thinning 23 weeks

So 2 weeks ago I was in the hospital to stop contractions. They measured my cervix and it was at a 4.1

A week later I was hospitalized again with more intense contractions that they thankfully were able to stop, but the next ultrasound showed my cervix was now at 3.4

I know that’s still good but worries me it shortened within a weeks time at just 22-23 weeks. Has anyone else had this happen but went on to deliver full term? I’m so scared to have another preterm baby. 🥺