How Long Does It Take for Tendonitis to Heal?

I think that I got tendonitis from running. At first I thought that I had somehow sprained my ankle because of where the swelling is. But then I was reading about tendonitis and realized that that's much more likely. Especially since the shoes I was wearing don't allow the ankle to roll and so it would be difficult to sprain the ankle in them.

I normally wear tennis shoes which have about a one inch heel to them or office shoes which have over a 2 inch heel. My running shoes have probably a 2mm heel. So it is very low to the ground, almost like being barefoot.

Apparently such a drastic change isn't really good. I thought that it would be okay because I walk around barefoot so much, but maybe my tendon just wasn't stretched out enough before.

I can hardly wait to go running again but my feet are barely allowing me to walk, especially the left one.

How long does this take to heal? Anything I can do to speed up the healing process?