At what point do you consider periods irregular? More specifically, if over the course of 8 months you’ve been between 28-32 days...is that considered regular or is it too much of a variance?

I’m just wondering because I consider myself fairly regular but today is only day 26 and I’m pretty sure my period is here (cramping, very little bright red blood) and it’s very early for me. Wondering if I’m not so regular after all?