Irregular period at 39? Women only please.

Hi Ladies,
Since I’ve stopped breastfeeding my daughter (she was 2) so it’s been almost 2 years now, my periods are all over the place.
22 days, 30 days, 25 days and today 20 days.
I’m freaking out a bit – has anyone else have this happen?
I’d love another baby but not sure I’m ovulating.
I’ve spoken to two doctors about it and neither were phased, one said ‘Yes to be expected at your age.’ I’m only 40 but is it?
Love to hear of other stories so I know I’m not alone, maybe I should freeze some eggs just in case!