Put down the stabilizers. When you get unhooked, and level, the camper is resting on the suspension, with the weight as is, and center of gravity, where is. If you extend the slides, the weight and the center of gravity will change, and it will cause a suspension change, and you will not be level any more. The stabilizers are are to limit or prevent suspension movement.
Hope you had a nice first trip and have many more.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT