light bloody discharge

[woodenmannequin.livejournal.com]

Since Sunday for only a couple hours during each day, there's been a very light bloody discharge. I'm not on my period, but even if this was my period, I'd be worried, as I usually have much heavier of a flow than this. I haven't had sex lately, and I'm pretty sure it's not a UTI because the blood is coming from my vagina and not my urethra. Any ideas what this could be? Think I should just wait for it to stop, or should I see someone? Thanks in advance!