Some aneurysms are not of concern until they reach a certain size. Possibly this is the situation, here. But you need more detailed information.
The CT scan report should contain a recommendation from the radiologist. What was the recommendation? If he recommended further imaging, I would infer that he has some concerns, either about the aneursym or about something else that he saw. If, on the other hand, he says something to the effect that he has no concern, and he does not think any further action needs to be taken, then maybe you are in the clear. Either way, I think I might want another opinion on the matter. But the report should give you a good idea how big a deal the radiologist thinks it is.