Recently I went and got std Tested for chlamydia and came out negative luckily, but kept getting stinging even though I get cystitus pretty much a lot of the time... Any then i was treated with anti-biotic for a urinary tract infection and i think its coming back or there is something else wrong with me as it stings when i pee and if i put a tissue up my vagina after peeing there is a brown light substance but with no odor.. Any answers to whats going on?? :-(