@kate2018 Here is my experience with a bad bone break at (barely) 5 years old. I am 36F so this was in 1990.
TLDR: Crutches races were super fun and recovery was a breeze. The accident/ hospital memory is still vivid, so good job keeping your cool.
Long version:
You did great and you WERE Superdad. I commend you because keeping your cool is tough in that situation.
I fell in a very deep pit while on a family vacation to Mexico. I broke both bones in my lower leg quite badly. It took a while to get me out, longer to get to a hospital with a working x-ray machine. In the back of an old VW van with shit suspension on shittier roads. It hurt like hell on the ride. I don't remember much from that age but I remember the pit, the car ride, and getting my bone set like it was today. Oh and the tetanus shot (don't ask what was in the pit).
It helped a lot in not being super traumatic that my parents were level headed. My mom was emotional but comforting and reassuring. My dad was very matter of fact. "Yes that is broken. Let's clean you up and get to the hospital" This is how I handle emergencies to this day so having a good example can be a lifelong benefit to your kid.
I was fearful for a long time of going back to Mexico. These were semiannual trips that I dreaded for a couple years, but I got over it once we were there. Your kid might, but might not link the park with the trauma. My advice is actually not to avoid it for very long so it doesn't build up in their head.
Your kid shouldn't be in much pain if everything is set right and stabilized right. I honestly didn't notice and definitely don't remember any pain after my cast was on. So don't worry about that from here on out.
I remember getting really good on crutches and racing my dad's disabled friend anytime we got together. Make adjustment to their limited range of movement as fun as you can.
The cast gets gross. That's all I can say about that. No keeping it clean at that age. Just accept it and don't badger your kid about keeping it clean.
Stay super dad. Keep it matter of fact and reassure your kid that these things happen sometimes but NOT ALL THE TIME.
Make sure you still go out and do fun things during the recovery and don't limit your kid if you can help it (except probably no pool haha). They will figure out and adjust to their limitations on their own.
And work on telling the story in a super embellished way that only dad's can. God knows my dad's version got to 30minutes long by my teens.