28 day cycle; now 24 - should I be concerned?

I'm 38, got pregnant fairly quickly and gave birth to DD about six months ago. Unfortunately I've had an unstable pelvis and so I want to give my body a rest before TTC again as it was very painful and interfered with me being able to care for DD.

Anyhow, on my ob's recommendation, I have been charting mainly for contraceptive reasons at this stage but with a view to seeing what my cycle is doing as obviously my fertility is likely to be declining at my age.

Now I'm in a minor panic because my last three periods have been on a 28 day cycle but my current one arrived after only 24 days.

Should I be worried? I know that a shortened cycle is one of the first signs of reduced fertility or does it often take a while for periods to settle down after childbirth? I've also been under quite a lot of stress the last few months so that may have been a factor.

I'm not taking temps at this stage - just noting when my period started.

Fiona - could be post-partum cycles taking a while to settle down.

Fiona,
it could just be your cycles settling into a pattern.
I had my first child at 40 and prior to that had a very regular 29 to 30 day cycle with an Luteal Phase of 14 days (ie. the time between ovulation and AF) and ovulating on day 16. when I got AF back at about 6 months postpartum my cycle changed to 26 to 27 with a few very short 24 day cycles. I still ovulate on day 16 so my LP is short. shorter or longer cycles do happen as you get older but changes do happen post partum so hard to tell really.