Big Fat Bloody lip

My son is like me he learns the hard way. My mom told me when I was little not to touch the Iron it was hot and would hurt. What did I do, I touched it and got burnt. Never did again.
Now, my son last night was sitting in his plastic toddler chair. He slip his legs in the hole under the arm rest. I say "don't do that Robbie you will hurt yourself". He ignores me and leans forward and fall face first on the floor before I can get across the room. He screams. I run to get him, assuming he is okay, because our floor has those foam puzzle pieces. He looks up at me with blood all over his face, he looks like a vampire with a fresh kill. I wipe him off and examine him. His teeth went into the back of his lip inside his mouth. So, he has puncture marks inside his mouth and on the outside it is purple and swollen. I have to get a picture of this. He is only 19 months and he has had one flat lip and previously a black eye. I hope he has learned from this.