Thanks for providing more information.
Insoles come in 3 varieties - off the shelf, semi-custom and custom.
Semi-custom are usually the best deal since custom are very expensive.
All inserts wear out after about 6 months of use.
With shoes, make sure you have the correct size - length and width.
You can get insoles in any shoe store ore shoe section of any pharmacy like
Custom made insoles.
Spenco insert. It is cheap, thin and flat, and it absorbs almost all impact to the foot.
For sports you can consider Softec Response Footbeds
For dress shoes,you can consider Thin Casual Footbeds
Even take short breaks of rest while doing work.
As you have lower back pain so you can also consult your regular doctor to rule out associated herniated disc,nerve compression at lumbosacral spine.
Use analgesic ointment/spray on lower back and apply warm compresses.
Also take OTC Motrin.
Start a multivitamin supplement.
Hydrate yourself with plenty of fluids.
If your symptoms'll persist then consult a podiatrist for further evaluation and management.
I hope this helps.
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