I haven't urinated for 6 hours now. This happened yesterday too. I was outdoors a lot both today and yesterday in these hot days. Last time I urinated, it burnt . I drank lots of water after that and it's been 5 hours or more that I haven't urinated till now. I am 18 year old male. I feel this very slight discomfort or kind of a tinge below my right ribcage and it's only there when I sit and it's not at all persistent.