I've made seven cross-country trips in the last two months, pulling 12K to 15K on the loaded side of the runs. Las Vegas to Nashville and back. I'm setup pretty good and made some adjustments during and after the first two trips. Once the rig is "dialed in" it is just a question of routine maintenance.
Check carefully at every fuel stop - tires, wheel temperatures, suspension. Always check truck and trailer tire pressures every morning before heading out. Know what the recommneded tire pressures are for your load and be sure, absolutely sure, that is what you have.
I have been lucky and spotted nails in two different trailer tires before they caused a problem on the road. It is much better to change tires in a Flying J's than along side of an interstate with cars wizzing by at 75 MPH+.
Other than traffic, lane changes, and hitting the right exits, after the first day you may find that it is easy to "get in the zone" and reduce the stress. Get your truck and trailer in good shape, maybe sign up for the Good Sam's Club Emergency Roadside Assistance Program, and have fun!