I don't understand! 💔

I'm 4 days late on my period but my test still come out negative! I'm pretty sure I'm pregnant but I don't wanna get my hopes up but my period always comes every 22 days sometimes a little later but no later than 26 and it's been 31 days now and still nothing ! I was suppose to get my period on dec 3rd according to my clue app but usually I always end up getting it a few days before and sometimes exactly rarely exact but sometimes and I'm already 4 days late according to my clue app any ideas ?