I have burning sensation in my vagina which increases during night. There is no redness or no itching. Just some clear vaginal discharge which is more than normal. I haven't had sex from past 8 months, no infections in tests and got myself tested for hiv & other std which are tested through blood sample. I drink 4 litres of water daily, the burning reduces but doesn't go away completely. It has been 6 weeks now. I got myself physically examined too but doctor said no UTIs.