It sounds to me like you did the right thing! and consider that in situations like this there may be no right or wrong thing, just life.
But since you weren't happy or satisfied working there I'm still gonna say it was the 'right' thing to do.
Your new job really does sound awesome! I want!
I think its important to love what you do. So if that job didn't leave you feeling fulfilled at the end of the day, it was time to get the heck out. Now you have time to work towards something that will leave you feeling satisfied at the end of each day.

and since your comics and art are so good you could use that to pick up some extra money on the side :)
hope you start feeling better!