4 days late... negative tests

So ladies! I’ve been TTC our second child for about 7 months. After stopping BC my period was pretty regular every 28 days. Last month I was a week early and AF came on cycle day 21, this month it’s already cycle day 31 and NOTHING! I took a first response test and it was negative. Took a few other brands and still negative. What is going on ?!? Is it too early to rest, is AF coming? I’ve had cramps off and on, swollen breasts and everything. So confused!