Stabbing burning pain in foot arch, with a hard lump. also swelling in ankle,unable to bear weight. what's wrong?

Plantar Fibroma: Though I have not examined you, it sounds like you have a plantar fibroma, which is a thickening and enlargement of the plantar fascia. They usually hurt if they press on underlying structures, or are getting very large. Try stretching and icing with anti-inflammatories to alleviate the pain, but the lesion will usually not resolve on its own. See a local Podiatrist for treatment options