Before becoming pregnant with DS, my cycle was 28 days. I got my period back when he was only 6 months, and it became a regular 26 day cycle very quickly. It remained 26 days through the next year and a few months until I conceived DD, May 2010. DD is 16 months, and my period returned when she was 11 months. Because I'm still breastfeeding and not so far out PP, I wasn't surprised that my period seemed "strange" - the first two coming only 21 days apart. But then the next one came 21 days later. And the next one 21 days later. I've now had 7 cycles PP, all 21 days apart on the dot.
What is this?! Is it normal to have such a short cycle? Is it normal for my cycle to have shortened by so many days? I am not quite 23, and was only 18 when I got pregnant with DS, so I don't have much time of actually observing what is typical of my cycle, because I simply didn't care as a teenager, and then I had more than a year and half off of having one at all!