TMI stomach issues, if I pair IF with a low calorie diet, may this cause constipation?

Asking because I have recently drastically changed my diet/fitness to get ready for a wedding. I cut my calories down to 1200(I’m only 5”4F) and have been fasting but seems like this has made me constipated or less frequent bowel movements from eating way less. via /r/intermittentfasting https://ift.tt/HU1kXVm https://ift.tt/Rrystw3