Player glitches out with boats

When I place a boat down in water close enough to land to walk on, I touch the boat and the screen just shakes and I can't move my head,  and the same happens when I am on top of a boat. Sometimes when I am in the water and I try to get in the boat, it drops me right through the boat and I can't get in it. When I placed it down on the water, the blocks I was standing on and the water were the same height.