I had a negative colorgaurd test in september. today i had what looked like a tiny bit of mucus blood on stool. should i worry about this?

Cologuard tests can have false positives & false negatives. If you only observed a tiny amount of very red blood on your stool or toilet paper, it more than likely was from a benign source like a tiny anal fissure, mild rectal irritation or hemorrhoid. I would observe for more showing of blood,abnormal bowel habits or larger amounts of mucus in which case you should notify your physician.