I have major pain under my feet, my heels are very painful especially when i wake up in the morning or if i sit and stand up. i cant even step comfortably which causes me to change the way i walk. its been a few weeks.not sure what kind of dr to see?

Heel pain: Sounds like plantar fasciitis. You can get a wooden foot massager https://www.chemist.co.uk/source-balance-wood-foot-massger.html , try rolling it over an frozen water bottle , memory foam insoles, motrin if not allergic and there are night braces https://www.braceability.com/products/padded-night-splint-foot-boot. If does not work may need injection F/u/ w/ podiatrist ( foot doctor)

One possibility : The previous response is very thorough except for one possibility. Custom orthotics when made properly can be effective 90% in my practice