Late period negative test

So my period is late only by 1-3 days but I have been extremely regular for over a year since getting off birth control. My average cycle is 29 days with it sometimes being 30 and one time 31 hence my 1-3 days late time frame. I have taken several tests in the last three days, albeit cheapy ones, but they all come back negative. We are ttc so I am hoping for a bfp but I don’t know what to think with negative tests but no period. I had some kind of cramping and aches in my lower abdomen around the time I would have gotten my period but it was not my usual period cramps I get on the first day of my period typically and then it never started so I am not sure what to think. Thoughts? Could I be pregnant or is something else going on?