about two months ago, i passed out and hit my head right side. only out for a few minutes but was confused when i awoke. did not remember what happen. i had a big knot on my right side of my head. about two days later, it look like someone hit me in the eye. i had a black eye. after two or three weeks black eye went away but i still have a small knot on my head that feels tight at times. i am concerned and the doctors said it would go away soon. how long? is this normal? what should i do now