Why do my calfs hurt when stretching my hamstrings (i.e. touching or trying to touch my toes)?
When you touch your toes you are stretching all the muscles down the back of your legs. Maybe it might help reduce pain if you do some calf stretches everyday. You can do this by standing on a step with just the balls of your feet and raising yourself up and down to a limit that feels comfortable to you. Over a time that limit will increase as you become more flexible.