I think I'm pregnant but I'm not sure??

my period was supposed to start a couple/few days ago (or weeks according to glow but I think that's bs) andd it hasn't, I've been having cramps and like pms emotions and everyday I expect AF be here already (cause the only time I get cramps is when I JUST started my period, that's how I know when AF is here) but it hasn't started for some reason? idk how long I've been having these pms like symptoms, and I've been having horrible heartburn and I woke up almost throwing up, like I could feel I was about to but I didn't thank god. sorry this is so long but I just want answers and I can't get a pregnancy test right now. thankss. also my AF is always like right on time, never late so it's weird. maybe just an irregularity idk.