Nice job on the truck. And it's good to hear the towing went without a hitch
Your trailer does look a little nose high in those pictures, and I wonder if you've left yourself enough clearance between the bedrails and the trailer. It's sometimes hard to tell from photos, but 3" would be dicey.
The problem as I understand it is if your trailer isn't level, there's more of the overall weight being carried on the rear set of trailer tires, and premature tire failure can occur. Mine's pretty level; even so when I did have a blow-out it was the rear tire on the trailer that went.