Should i be worried that my doctors office called me to make an appointment following an er visit with abdominal ct and blood work?

Not necessary: Sometimes it is better to explain findings of test in person. It does not mean that you absolutely have something horrible but your doctor might want to discuss a treatment plan.

Not really : Depends on what they found. All physicians have different way of practicing. Some will give u info over phone while others will give it in person. If er did not say anything serious, it prob is nothing serious.