We drive from SW Michigan to Ft. Wilderness with a camper most every year. The tow vehicle, a minivan, is my primary vehicle so I am used to driving it.
We got a new and larger camper last year where I didn't have as good a view from through the back window, plus it would sway a bit at higher speeds (esp near tops of mountains), etc. Also had electric brakes for the first time.
You do get used to the feel and your view.
Some things I would suggest to help you feel in control and cut down on the anxiety:
1) Have your trailer/camper serviced by professionals before leaving (including a thorough check of all things, repack the wheel bearings, tire pressure, etc.)
2) With the camper, we only have two tires and had them blow out on us one trip ... now I always pay for new tires every couple of years prior to leaving
3) Have your tow vehicle serviced a couple of weeks before going (just in case you have any leakage from them not putting drain plugs back in tight enough) ... including brakes, tires, etc
Now you can have piece of mind that your RV and tow vehicle are in good shape.
4) Be familiar with directions ... study the maps and know where you want to go -- find out about any major construction and think about a possible alternate route
5) Get on the road early so you don't have to panic if you run into traffic
6) Have beverages/snacks/sandwiches accessible ... including caffinated beverages for the driver
7) Plan to stop at least every 2 hours to let everyone stretch and then walk around your RV to double-check connections, tires, etc
8) Make sure the kids have books, tapes, etc and that there is a blanket(s) and pillow(s) for those that want to sleep or get cold
We normally get on the road by 3:30 am and then have a hotel room booked for Tifton, GA (about 4.5 hrs from Orlando) for the night ... usually get there about 7:30-8:00 and then order a pizza. The next day we are on the road by 7:30 am and pull into Ft. Wilderness by noon ... giving us the rest of the day to set up (during daylight) and enjoy the pool, etc.
Have fun ... try to control those things you can, and forget about those things you can't.