Sherlock/ John gets injured (nothing too serious, pulled muscles/ torn ligament/ broken bone/ etc) and the other one starts getting serious sympathy pains.

The injured party is touched but a sort of annoyed that the other is taking their thunder a little. The one with sympathy pains is trying their best not to make a fuss but god damn it feels like it hurts like hell.

Prompted because it's happening with me and my best mate at the moment. =S