Hello and welcome to HCM
An examination of your is required to make a diagnosis.
However, on the basis of history as you have mentioned there is a painful hard swelling under on the sole of foot.
The cause of the swelling could be your job which demands to be on feet for long time.
Now this swelling could be a bony growth or a soft tissue
Soft tissue growths include swellings arising from muscles, nerves, fibrous tissue, blood vessels and lymphatics.
The first step is to get a X-ray foot. This will show whether the swelling arises from bone or soft tissue.
If it is a bony tissue then the bony overgrowth may have to be removed surgically.
In case of soft tissue mass, a FNAC can be done. FNAC will determine the type of cells present in the swelling.
On the basis of these investigations a surgical removal of the swelling can be done, subsequent tissue examination and exact characterisation of the swelling.
Thanks and take care
Dr Shailja P Wahal