I'm a stage IV head and neck cancer survivor. I had chemo and guess what else?
Yep... Radiation! I had radiation on my neck 5 days a week for 6 weeks. 30 treatments. Enough radiation to burn the skin off my neck and turn my throat into a swollen mess rendering me unable to eat and requiring a feeding tube for a month during recovery. Ohhh... before each radiation treatment, I had a CT scan when they pinned my head to the table with a fiberglass mask so they could make any adjustments to the radiation beams before each treatment. That's 30 CT scans and radiation treatments in 6 weeks. That's not even counting the x rays, CT scans, PET scans and MRIs before, during and afterwards. Add to my personal experience that there is not one documented case of any type of cancer attributable to scans and your thoughts and posting this on an anxiety forum? I rest my case
Getting help with the real illness you do have would be the most beneficial approach to alleviating your symptoms and fears.