I was playing basketball and my hand was positioned wrong and the ball slammed into my thumb when it was still extended, and it hurt'd like hell for a few seconds. Now it's sorry when ever move it to the right.
Ice and a finger splint. Don't bend your finger, it'll cause more damage. Try wrapping a bandage round both your finger, and half a pencil or something. This will keep it straight and it will heal quicker.
Just saw you said it was your thumb. It could be damage to the muscles in the palm of your hand that have sprained. Ice aswell, and try not to move it. That's all you can do really
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