Iin, after walking, to need to stretch my legs until they painfully hurt?

Everyday when I get home at the end of the day, after walking for about 10-15 minutes, my calves feel really tense and stiff. If I even slightly stretch my toes down, my calves immediately start to hurt really badly (I think it's from the lactic acid). But my calves are so uncomfortably tense that the only way to make them feel alright is to purposely stretch my legs in this way so that they feel really painful, and then to bear the pain as long as I can. It's really unpleasant, but if I don't do it then they feel really uncomfortable for the rest of the day. Is this normal?