Im glad your jaw went back into place.
If you can you should see a regular doctor, explain what happened, and make sure you didnt/dont have lockjaw.
Below is what the web says when running a search for "What causes someones jaw to be unable to close all the way"
"A tight jaw can happen for many reasons, such as stress, temporomandibular joint disorders, grinding the teeth at night, and tetanus, also known as lockjaw."
So it would be good to know what it was before it happens again, and make sure it isnt tetanus.
Sorry about sounding like a Mom, but sometimes things can be serious.