I don't consider the trailer you bought to be large at all. Especially since you have more than enough tow vehicle.
Buyers remorse is not a good feeling, but I think some people get it naturally. When I buy something new, I'm the type of person that loves what I've bought. My twin brother is the opposite. He gets buyers remorse before he even buys something.
I think you'll appreciate the extra size compared to a smaller unit. The Minnies are a really nice unit, no reason to regret anything. In the world of travel trailers, you have a pretty small unit.
I bet after your first trip you won't regret it at all.