Can’t sit in drivers seat for extended periods without aching…anyone else had this issue?

Find a good chiropractor and get weekly adjustments until you feel better then once every 2 or 3 months is enough. Walk at a brisk pace for 2 miles a day get your blood pumping. When driving raise the seat up off the floor and sit up right. It doesn't look cool but setting it down low will kill your back. I had a slipped disc and nerve pain so bad I couldn't even walk a couple of years ago. Miserable. It took me about 5 weeks physically rehabbing it doing the above (plus a half dozen different exercises for 30 minutes a day) to get functional and back to work but was more than a year before I felt like my younger pain free self again. Also important, stay hydrated.