Hi Tracey,
First up, take a breath, you will be okay. The way I like to look at it is that I am no sicker now than I was the day or week before my diagnosis, the only difference is that now I know I have it and I am doing something about it. So are you.
Are you doing your meditations and exercise lately? I find both help but long walks and boxing have been a great help.
Take one day at a time. It sounds like you have had some battles in the past, use the knowledge & skills you have gained from dealing with them to deal with your cancer.
Hang in there and take some deep breaths, you can do this.
cheers
Mira