Shorter periods normal? Early menopause ?

I have always had heavy periods and usually they last upto 7-10 days but for the last 5months my cycles have changed and are only lasting 3-4 days max with light/medium bleeding which is very unusual to me. Nothing has changed in my diet or life that I could think would impact my periods, I’m also not on any birth control and I turned 30 last year don’t know if that has anything to do with it but has anyone experienced this? Is it normal as you get older like the start of menopause or something ?