Help me understand what irregular periods are!

Irregular periods are when you don't have a period for whatever month it is but you start the next month right?

I don't have this issue like I did back in 2018/2019,but my period comes every month,but not at the same time as in date which is normal.

Sometimes my cycle comes early and sometimes a little later,and my obgyn doctor speculated I had PCOS,but never did any testing to confirm it.

Although my cousin who is an registered nurse says I don't have the symptoms of PCOS. The facial hairs,and I can't remember what else she name.

What supplements from Walmart, Walgreens or Amazon are good to regulate periods?

There an app that you can log your periods and tells you if your cycles regular or irregular? Just saying! 🤷

My periods ranges in 32 to 35 days at times. I only bleed for 5 or 6 days.