Period question for ladies in their mid to late 20s

I came off birth control almost two years ago now and have been adjusting to my cycle. I have had pretty consistent periods and symptoms of PMS now for about six months and it's just so vastly different to what it was when I was in my teens pre birth control.

I'm just generally curious if others have experienced this and if I should be expecting some big changes as I approach 30. (FYI- no children, never been pregnant and not TTC ATM).

What's been your experience?