I had the exact same thing happen to me 20 years ago but never told the doctor. It only happened once. I guess I would have followed up on the problem if it had showed later. I was 45 years old at the time if that will help any and I am still here . What I did have about 6 months later was a Kidney Stone show up. That could be what's happening in your case. I would also be worried if I had other symptoms . I will tell you this. If you go to a doctor be prepared to be put through all types of tests. I had a Cystoscopy done last year because of blood in my urine and of course my age. Everything turned out fine. If a doctor suggests you have this make sure they put you under. They might suggest you get it done at their office. I am telling you now, make them put you to sleep. I am no doctor but sometimes little things like these happen and most of the time its nothing to worry about. Good luck. Tom