Shoud i be concerned about having 1 cat scan on my abdomen to check for appendicitis?

Unless you work in a field where you are exposed to large amounts of similar frequency radiation a single CT scan is not a health concern. In the case of appendicitis I am somewhat surprised that the ct scan was used as a first choice instead of a cheaper ultrasound, or Doppler sonography, but if you are obese it can be hard to tell on those two instruments. Between a simple blood test and an ultrasound in most cases that will detect appendicitis, though a ct scan can be more accurate. I just personally prefer the cheaper ultrasound blood test combo, over a ct scan and only doing a ct scan if those two are inconclusive.