For the past 3 months, it burns when i pee. the burning seems to subside when i drink a lot of water and have peed a few times. what could it be?

Dilutional effect: Burning on urination can be from an infection, too much acid in urine (too many carbonated beverages), bacterial/yeast vaginitis, inflammation of the urethra or vagina from chemicals (douche, bath soap, feminine sprays). For the first two, water will make the urine less concentrated & your symptoms may resolve, returning when your stop drinking water. Need to check a urinalysis & if (-) an exam.

Infection: Could be infection or a disease such as reactive arthritis. This requires evaluation by a physician.