I Have Mild Pain In The Right Side Of My Right Hand From Tennis?

Ive noticed pain in the right side of the palm of my right hand (side of the pinky). it extends from the knuckle of my pinky to my wrist. My coach suggested tendinitis but i havent gotten it check out yet. I can especially feel the pain in my forehand and overhead. and also serves. not much in the backhand. any suggestions to treating it besides icing it? or actually what it might be? the pain is only there if i put pressure on the hand or when i play. not much when the hand has no pressure