Don't overthink it so much Marie. After the Oncologist visit, you will probably be assigned an Oncology nurse that you can call or text with concerns or just because you feel down. There will be all kinds of counciling available and other resources.
Take it day by day and don't worry about things you have read and what others experiences have been, your cancer team will custom tailor your treatment just for you. My first major cancer journey differed from my current one. While the first one was, time is of the essence, my current one is wait and watch with testing every 6 months. The rate a cancer grows, determines treatment.
You will learn how Oncology and Hematology are connected and how various blood test help an Oncologist chart and follow your cancers response to treatment. Your appointment tomorrow is just one of many you will have. I hope the news is better than you anticipate. Hugs!