If i've had 4 ct of the brain n a 7 month period am i going to get a tumor i'm 22 years old ?

Not likely: The question I have is WHY you had 4 ct of the brain n a 7 month period. Usually a 22 years old has 4 ct of the brain n a 7 month period because the people who do the later head ct don't know about the earlier cts because the person getting the cts of the brain (i.e. YOU) didn't tell them about the earlier cts, so that the later ct orderers didn't know the later cts were UNNECESSARY.