I was loading the back of the vehicle with bags and the back door/hatch came down on my head and gave me a large puncture wound in my head. I have to go to the Urgent Care because of the extreme pain, dizziness and excessive bleeding. I could not get the bleeding to stop. I saw the doctor who cleaned my head and then he needed to quarterize my head more than once in order to get the bleeding to stop. I could not drive or operate any machinery for at least 24 hours and had to be under observation due to a possible concussion.