Short Cervix

Cassie
Today I went it for my 20 week ultrasound and it was super painful. I almost cried from the cramping and lower back pain. Then the tech told me I had sludge in my amniotic fluid and a short cervix (2.7 cm). I have a doctors appointment soon but I'm a little nervous. These are all signs of potentional preterm labor. Anyone else in a similar situation?