Sometimes in life you just get in and drive. Every trailer I have hauled including in more recent times a Utility, Pop-up, 14 ft. TT and now my 25 ft. Dutchmen has a different feel.
For every TT and TV combination you drive you need to establish;
* How fast can I stop. Including really hard stops.
* How fast can I accelerate.
* How much swaying do I get, if any, when towing a straight line.
* How much side bumps do I get from trucks, busses and wind etc.
* How bouncy is the combo on rough roads.
As previously mentioned a lot of this is normal, particularly when you are towing something that weighs as much as your tow vehicle.
My standard advice to the first time buyer is to rent a TT similar to what you think you want. You learn a lot in a short time about pulling one of these barns down the road.
Good luck and enjoy the RV