Well, without an evaluation, it would be difficult to determine the cause of your pain. Possibilities that may need to be considered include stress fractures, ligament/
tendon injuries, infections, inflammations like fasciitis etc, spur formation, heel fat pad syndrome, arch issues etc. It is advised to consult an orthopedician for an accurate diagnosis and appropriate management. Meanwhile you could use some tylenol/ OTC NSAIDS for pain relief.
Hope this helps.
Take care!