Scared out of my mind...Please help!

[Brit-tastic]

I went to an endodontist today to have a failed root canal retreated. He retreated, and then after he was done told me that he would like me to come back this week for an apioectamy (sp?). He said the infection seemed really bad and just wanted to make sure it was caused by normal endondtic issues and not anything else, so he's going to send my root tip out for a biopsy. I'm currently freaking out, thinking I have oral cancer. Has this ever happened to anyone???