Tightness?

Additional Info: TTC since late October, 1st Baby

My stomache has felt so tight the last week or so! It's never been like this! Also alot of bloating. Last week I had my first period since coming off the pill (which I'm never hungry on so I don't eat much) but my stomache still felt very tight! I've taken the initiative to drink more water, could this be causing this? Any other ideas?