Vaginal burning with penetration for ~3 years have a normal pap, negative uti, yeast, trich, std but no other tests have been run. what should i ask to be ran next? probiotics didnt help.

Vulvodynia?: Genital pain in women, without obvious other abnormalities, is called vulvodynia. Need to be 100% certain there is no infection, and no hormonal abnormalties. You've had negative evaulation for some but perhaps not all possible infections that could contribute. Next step should be a gynecologist with special interest in vaginal infections, vulvodynia, and/or sexual health. Good luck!