Do yourself a huge favor

get a blood test done for thyroid.

I did a 25 day master cleanse last summer and it sent my body into a massive hypothyroid state. I actually lost most of my hair and my cycles because irregular.

It is a simple blood test that your doctor can order. That will help you rule out one cause. generally sudden weight gains and digestive problems are a couple of the symptoms of an underactive thyroid, there are many many others though.