Macroscopic Hematuria

[spotdog13]

Hi all,
About 1.5 months ago I suddenly had macroscopic hematuria while urinating before bed, without any pain whatsoever.  The color was not "blood" red, but a bit more dull, almost light brown/red (i'm fairly colorblind so that doesn't help).  Needless to say this caught me totally off guard and caused me to schedule a Dr. Appt where small amounts of blood were found in my urine (microscopic hematuria this time), no bacteria was found, and I was ordered to have a CT scan (without the illuminating dye) to check for kidney stones.  The results of this were negative and I was referred to a Urologist, who did a cystoscopy to check my bladder for problems.  The Urologist saw nothing abnormal, and my urine had no blood that day.  

About 1 month later right before bed, my urine was again light brownish red just like the first time.  I have not gone to the Doc again because I don't want to have more expensive tests for no reason.  I made the mistake of telling the Urologist that I am a distance runner, which lead him to write me off as experiencing runners hematuria.  However, the first time I experienced this, I had not run for 2+ days.  Everything I've read says that runners hematuria is typically experienced immediately following the run, which leads me to believe something else is going on.  I am 23M and active every day, but this is new and scares me.  Has anyone had a similar experience or have any advice on what my next steps may be?  Thanks in advance for any insight you might be able to provide.