Being constipated for 2 days while on my period.

I have been unable to go to the bathroom for the past 2 days. I'm getting worried that its possible that it could make me sick. I woke up feeling bloated and sick feeling I tried going but nothing. I have been drinking a lot of watch because I heard that it helps. I know that fiber helps but that's about it. What should I do? Should I be worried? And why Does this happen while I'm on my period?

(Being constipated is pretty normal for me but I get it longer when I'm on my period. I also have gluten intolerance and dairy intolerance.