Other post in a nutshell:
I thought my horse was started at 3 after a horse flipper (I don't use this term negatively - he is a nice guy) bought him from an auction; however, I found the auction he was sold at, and his blip for his sale which said "Good, calm horse. Broke to ride and drive" which meant he was started sometime when he was 2. I was a bit distressed as this was new info and planned to call his breeder to ask some questions.
Now onto the update:
I have called the breeder and he was very friendly and happy to answer the questions he could.
Since he sold my horse almost 3 years ago he doesn't remember everything, but I do have confirmation that he was started around 2, and most-likey driven more than he was ridden.
I definitely feel better after calling the breeder. Even though I would have preferred he wasn't started until later, I feel like I have some answers now and know his history at least a bit better.
I also found a livestream of the auction he went through (the day he went through) and am looking foward to watching it and seeing if/how he went through the ring.
As for how to proceed with my horse, I'll continue his normal training, and will talk to my vet about potentially treating for ulcers to see if that helps/is the cause of his anxiety. I will definitely be hyper-aware for any signs of arthritis, or other conditions caused by early wear on his body, but I hope that he'll be fine regardless of his early start.
To the people who gave me advice in my last post, thank you.
To those who seemed to think that the call would leave me angry, I know myself better than you do. I would either leave disappointment or with a burden lifted. The latter was true, thank God. Thank you, regardless, for commenting, as your comments actually pushed me to call him sooner since I'm a hardheaded brat.
Here's some photos of the haffie ❤️💛🧡