I think a brisk walk is a great idea. And keep on drinking that water.
Did you drink any diet soda? When I used to drink soda, I'd be terribly bloated. Also, if you are consuming more fiber than you're used to, that can cause bloating, too. Some people have that reaction to food allergens, although they're not aware they are allergic to a particular food. You might want to journal what you eat/drink and make note of the bloating to see if it occurs when you eat certain foods.
Women who behave rarely make history.