Short Cervix what to do?

So I'm currently 21w 2d & yesterday I went to the doctor for my 20 week ultrasound and was told I had a shirt cervix. And I'm now high risk for preterm labor but my baby girl is healthy and everything else looks good. However there are no known causes and since this is my second child and the first was a good pregnancy they are not sure why it's happening. So anyways I was given multiple options such as a research study to insert a ring to hold it together or stitches in addition to either inserting a pill vaginally every night. Im doing the pill but I'm so scared and don't know what to think or do as far as work and so on. Has anyone dealt with this if so what where your results and how did you get through it?