Did I make a mistake?

I think the decision you made is fine! That's awesome you're moving in to a higher level, just don't regret it, because that's a great accomplishment. However, if you really love playing football, the starter position would've been the best choice, but like you said, you like the family atmosphere, so that shouldn't matter. As long as you won't ever feel like you're missing out on playing football, you're fine :)