I know that, back when he had his stone surgery a year ago, he did the exact same thing -- was fine and then started bleeding almost a week after the surgery. Vet had said it was nothing to worry about, and it stopped as suddenly as it started and he was fine.
Obviously stone surgery is more invasive than the lump removal, but...could this be the same thing happening? Is post-op bleeding a few days afterwards fairly normal regardless of the type of surgery?
Otherwise, I'm going to guess it's from the stone. He seems fine...active, eating. ??
Poor little guy. He was having such an uneventful recovery until this. :(