I have cs6. the spot healing brush makes the area very bright and pixelated, it doesn't erase it. I have heard resetting it might fix any problems, but I don't know how to do that either. Very frustrated at this point
found out how to reset tool, and it worked. I will explain how, in case anyone else has this problem.
1. click on spot healing brush
2. go up to the top toolbar and find the spot healing brush icon
3. click on it and find the settings icon on the right
4. click on it and find "reset tool" option. this will reset your tool
so yeah there you go. this can be used with any tool that you have problems with