Not sure what to do.

I'm 4 days late for af, and I'm usually irregular. I have taken 4 pregnancy tests (FRER) but they've all been negative. The one this morning had an indent line on it with no color. The longest I've went without a period is 96 days. And there's no way to tell if it's going to start soon. I had cramps on 8dpo and my boobs have been sore for a while. But that could mean either. But what I'm really concerned about is that I'm supposed to start taking a new medicine to help some of my PCOS symptoms, but if I am pregnant, it can cause miscarriage. What should I do? Do I just hold off on taking the medicine until I get a period, even if that means I might wait for a really long time?