Anyone have their cycle shorten after they hit 40 and still conceive?

Im 42. My cycle has always been on average 29-30 days. Last month was the first time ever that I had a 22 day cycle. And I am thinking I'm about to have another 22 day cycle because today is cycle day 22 and Im cramping like AF is coming tomorrow.

So frustrating because my cd 22 is also 6dpo (according to glow app) which is when I had implantation cramps before. So i have no idea if these cramps are implantation or Af.

Ugh. Today is gonna be the longest day ever.☹️

Anyones cycle shorten and still get a bfp or am i just not ovulating anymore? I havent done opks yet so I really dont know.