Here's the deal- I've been regular with a predictable pattern of menstruation for a long time.

After initial start-up hiccups at 13, I was on birth control to help with cramping at maybe 15.
My flow would start with cramps, go a couple days and trail off, I'd spot for a couple days, and then have a grand finale flow slightly less or equally as heavy as I started with.
I'd cover a full 7 days.

Off of birth control for the last 3 years, I have a different pattern. I'm not sure how long it took to switch.
I'll have a pink-tinted wipe, or a bit of brownish spotting one day. Then I'll have 1 or 2 days of nothing.
Finally, I'll officially start with a heavy flow- I'm changing a cup every 4 hours the first day. I'll flow less heavily, but consistently, over the next 2 or 3 days and then stop. The stop might end in spotting or just a little bit in the cup over a full day, or with just an empty cup overnight.
So I consider my flow to be 3-4 days, depending on the spotting afterwards. If you count the pre-herald spotting or color, it might still cover 7 days total. (But I count that heavy day as day 1)

I started keeping notes in June, and last month was off of norm for me enough that I really thought I might have been pregnant temporarily.
Instead of 27 days, I had a 33 day cycle that ended with only two days of heavy bleeding from 1pm Saturday to Sunday night only. This was after only a giant clot Friday morning. Saturday, I had cramps like I hadn't experienced since I was a new teenager.

I'd been completely cramp-free for at least 3 years now, possibly more.

And now this month, I wiped a good amount of blood at almost midnight Friday. Overnight the cup was maybe 1/4 full.
And there has been absolutely nothing since. I'm waiting anxiously for something to happen.
That was not the spotting like I got before, but neither am I bleeding like last month. WTH is up with my period??

I had thought based on advice here that the last cycle could have just been one of the "wonky" ones. But this one isn't normal either.

Have any of you ever had your regular pattern suddenly change like this? If so, can you think of anything to have triggered the change? Did it ever go back?