Period almost a week late started mini pill two months ago

My average cycle length since getting my period back after having baby has been 22-26 days most commonly around the 22-23 day range. I started the mini pill two months ago and got my period on time, 22 day cycle. Well today is the 33rd day in this cycle and I have yet to get a period. Is this from the pill or is it more likely that I am pregnant? I took a test maybe 3 days ago and a clear negative. Should I just test again? And if I'm not pregnant is it normal to have cycles be so erratic after starting the mini pill?