I have pain in my left heel. (The bottom of my heel) Every step I take is painful. I didn't step on a rock or peeble i.e. stone bruise. I don't remember doing anything unusual to injury my left heel ...
I am a physical therapist and frequently treat this problem. Most likely you have plantar fasciitis. I would recommend using ice on your heel (no heat) 10 minutes at a time a few times a day. I do not like using heel or shoe inserts that have cushion as you more than likely need more stability. Wear a good running shoe not sandals. Stretching your calf muscle will also help.
To view pictures of stretches and other treatment details for this condition, visit www.joint-pain-solutions.com/plantar-fasciitis.html
First of all get a professional diagnosis (not over the internet) before you spend more time, money and effort.
I am dealing with plantar fasciitis for more than a year now and I understood that treatment efficiency is very individual. If something works for one it may not work for the other. There are many treatment techniques that you can try.
I found a very informative website in: http://www.plantar-fasciitis-elrofeet.com
Take care & Good luck