Spec’s

Hey everyone I’m a 24 Male and for the last year I’ve been noticing a tiny spec of what looks like blood in my urine sometimes. It’s not persistent but i randomly notice it from time to time. Almost always at my home though. I’ve had extensive testing done including a cystoscopy and CT scans along with countless blood work and urinalysis and everything came back fine, at this point when I bring it up to my doctor they just tell me to monitor it but nothing is changed well at least I don’t notice it as much anymore but it’s still annoying at this point I don’t even know if it’s actually blood or not. I’m in no pain whatsoever and can urinate just fine.