The last two nights I have been experiencing severe, throbbing pain near my left kidney. There is almost no pain during the day and late at night it gets extremely painful. The last few days I have felt like I have had a UTI, and I assumed that was all until last night when I had extreme kidney pain. The last time I had sex was on the 14th, protected but I am not on BC. My period came at its normal time several days ago but it has been lighter than usual. I also read a cause could be due to dehydration, but of course I'm freaking out about the other possibility. Any thoughts on what it could be or what I should do?

UTIs are a common cause of kidney pain in women, and doesn't necessarily mean you will feel normal symptoms of a UTI. But then you have to consider that if you don't have normal symptoms of a UTI such as burning while urinating, then how long has it gone on in furthering damage to your kidneys. If you were a diabetic, it would present a major problem and you haven't mentioned any pre-existing conditions. In any event, get to your doctor to be tested for a UTI and get it cleared up.

It could be a kidney stone. You need an xray; see a urologist