My knuckle looks and feels like it s sliding out of place. When I straighten my hand it appears to dip down slightly so there is a prominent inward curve (unlike the other side). I was stretching my arm and there was sudden pain and all my fingers, wrist and arm tendon appeared to lock. It s slowly unlocked now... It s stiff and I can slowly bend it but there s no pain at all, even when it moves out of place. What should I do?