Uti-like vaginal discomfort that goes away?

Hi, I have had a couple of UTIs and been noticing something recently. I have the kind of vaginal discomfort that is very similar to a UTI when I am dehydrated, and then when I drink a bottle of water or something it seems to go away. Never lasts for longer than a day. No kidney pain, no urinating small amounts. Just discomfort. Is this a lingering UTI? Is it something else? I am not home currently but plan to take an at home UTI test when I get back. Really don't think it's a UTI though due to it going away and not changing how much I pee. Thanks