Thanks for choosing health care magic for posting your query.
From the description that you have given, it appears that you are probably having an anxiety
disorder and you will tend to worry more than what is required actually. Yes to some extent you are right that CT scan
does cause radiation
exposure but then if its an occasional radiation exposure, you need not worry. You should worry only if its a regular exposure like exposure to the technician who performs CT scanning.
Regarding you anxiety disorder you should meed a psychiatrist
who would like to start you on some anti-anxiety drugs and also would like to treat you with some talk therapy
Hope I am able to solve your query.
I will be happy to help you if you need any further clarifications.
You can contact me on the following link:
Wish you good health!