Sunday and Monday I got hit by some virus. I basically had the worst diarrhea I've ever had in my life. I moved my infant son's wet wipes and butt paste into my bathroom it was so bad. I pretty much stopped drinking and eating, because 20 minutes later it would be coming out of me, and I could barely sit as it was. I dropped 7 pounds in two days. I think that I was pretty dehydrated.
Tuesday I go back to work and I hit the gym afterwards, running my usual 7 miles on treadmill.
Wednesday I take off from exercise.
Thursday I went to the gym again. I had an iced-tea at breakfast and another at lunch. I took a leak before running. I ran my 7 miles, grabbed a drink of water, and had to urinate again (which is strange after running). While doing the deed, I glanced down and see that I am peeing what appears to be straight blood. I was freaked out. I'd never had that happen. Five minutes later I had to pee again and the same thing happened. I was in no pain whatsoever, so there was no indication beforehand that something might be wrong.
I took a quick shower and went straight to the Prompt Care office near the gym. 45 minutes later I was providing a urine sample and it looked pretty normal (if not a little on the dark yellow side). The doctor told me that test strips indicate that there is blood in my urine, and I should see my doctor again the next day. She said that she thinks that either I have a kidney infection, or that my vigorous workout coupled with my apparent dehydration made the fluid from muscle breakdown that occurs during such workouts to go straight to my bladder, undiluted. I am prescribed and antibiotic, just in case.
After I get home, I drank what seems to be around a gallon of water. I urinated a little, but not as much as I took in. Everything
looks normal.
I went back to see my doctor the next day provided yet another urine sample. My doctor thinks the issue is either the muscle fluid thing, or I have something like a leaky blood vessel on my bladder. He said that the test strips indicate blood in my urine, but 13 or so hours after the episode, that's to be expected. He will have the sample sent off for micro-analysis. If that comes back negative for blood, my problem was probably dehydration + excessive exercise. Apparently the test strips will be positive for blood if it is blood or muscle fluid.
I get a call back later in the day: urine normal, negative for blood. I guess the lesson here is to stay hydrated.

I really feel like an idiot now.