ACJ - I'm sorry to hear of your trouble. My road has been six years of oral cancer, not ameloblastoma, but here are a couple of thoughts.
First, know that it's normal to be scared when faced with potentially life-changing news like this. Second, it is also normal to presume the worst, and you will find lots of worst-case scenarios on-line. It sounds like you've already found that out but I would suggest you not dwell on those things (and you didn't jinx yourself by posting here!). Anxiety is not your friend right now and might make things worse. Take walks, do the things you love doing that take your mind off of this. Third, you need a support group. People you trust that you can be honest with and who will be honest with you. That could be parents, older adults or anyone what has been through something similar. Your support group might include a faith community. I have found my religious faith to be a vital part of coping and recovery. Fourth, find medical people you're comfortable with who are knowledgeable about this condition.
Good luck - keep posting and update your status when you know more.
Steve