helpful input appreciated

I had a baby 5/12/16. Had to stop breastfeeding due to complications with his tummy. Hormones went crazy and I had a whole period of time that I thought I was pregnant again. Then I had the lightest period ever that lasted 2 days Oct 1st. I used to have a 31 day cycle so was expecting period yeaterday. It didn't come. I am unbelievably exhausted, but also am fighting a case of the shingles. It's mostly cleared up but thought I'd put it in there. How long do I wait for period before I take a test? I don't want to waste money on a test again. Haha! Is it normal to take a couple cycles to get regular again? Appreciate your assistance!