Cycle day confusion

Hi everyone,

Last year I was diagnosed with PCOS after missing a couple months of my period. All last year, I never had a cycle that lasted shorter than 31 days.

This year, I have been lucky enough to have had a period every month so far, with my cycles still not being under 31 days long.

But my last cycle was 25 days, I was very confused when I woke up to my period this morning. My husband and I have been TTC since January last year.

Could anyone help clear up my confusion and what could be going on?