A painful bump. I let my Shepherd to pull his fully inflated knot out (we have done this before with no problems) but it seemed he grew bigger since last time, three months ago I reckon. He got stuck halfway out, no possibility of getting him in again. He started to cry and we have to exert more force to finish the maneuver. I saw stars and couldn't take control of my sphincter for a couple of minutes. Still hurts. He is happier than ever, but my other two dogs will have to be satisfied by hand for at least a couple of weeks. Surely an afternoon to remember ?.