You should be fine... You are well within the safety limits.
First off, it will take you I'd guess 16-18 hours to drive back, if you drove straight through. Going back through Alabama/Georgia and Tennessee, Kentucky, etc, the max altitude you'll be at is about 1000 ft. Maybe 1500 feet max, but I'm willing to bet under 1000. Most of your trip will be under 700 feet for exmaple.
For example... Airport elevations in these towns.
High Springs FL 90ft
Macon GA 354ft
Atlanta 1026ft
Chattanooga 683ft
Nasvhille 599ft
Ft Campbell 573ft
St Louis 605 ft