What is usually the outcome of a blocked salivary gland?

I went to the doctor today and was told I have a blocked salivary gland. I am 24 years old and the doctor said he felt something and wasnt sure if it was a tumor or a calcium deposit. I have had 3 CT scans of my neck and mouth before and nothing showed. I was told not to get anymore CT scans due to radiation. They want me to get another Ct scan to determine what it is that is blocking my gland. I am a nervous wreck. Are there any other tests that have no radiation that can determine whats in my gland?