Luckies,
I'm sure Dylan will be fine. I'll share this with you..
When I was a toddler and learning to run, my parents too me to the county fair. We were inside where there were displays of iron stoves. My mom turned her head and let go of my hand only for a second and off I went. I ran head first into the corner of one of those stoves.
I knocked both of my two front teeth ENTIRELY back up into my head. They were completely invisible. Needless to say, my whole face was a bruise.
The next morning after emergency room visits, we went to the dentist. One of my teeth had begun to descend and the dentist told mom to let them come back down on their own. And they did.
Now, one of my teeth has a tiny chip on it. The baby tooth chipped the root of the permanent tooth when it went up. But otherwise, you'd never know it happened.

...and, I wouldn't either if they hadn't told me the story.

So don't worry. It hurts you more than him. He'll have forgotten all about it much much sooner than you and his little teeth and lip will heal.

Children are so much tougher than adults!