Can anyone help me? I’m so confused

I’m currently 22 weeks pregnant and just got out of the hospital after having contractions throughout the day and night. They did check and I wasn’t dilating any which was a huge relief for us! I’ve had two premature babies and I’m terrified of it happening again. The only thing I’m confused about is on the transvaginal ultrasound report it said trace amount of fluids found in the cervical os. What does this mean? They didn’t explain anything to me and I see my OB Monday to re check everything. I’m a nervous wreck!