Late or Irregular?

I've had my normal period symptoms (migraines, nausea) but now only SLIGHT tolerable cramps and no spotting. According to the calendar I was supposed to start my period today, but I haven't 😕. So it gave me until Sunday, but my nerves are so bad right now! My partner and I use condoms and sometimes pull out method. But last time my period was a day late, it came. The times of the month have been different for about 2.5 months now. I have been stressed lately. I'm hoping I'm not pregnant because it's too soon for me. Any thoughts!?