Good on you for managing to cope while having your scan.
I have severe anxiety and have been house bound for a few years. I was so bad I couldn't get out of my bedroom. I have been working with a therapist and attempting to move away from my safety zone.
I find breaking down fearful tasks into small, achievable steps is the way to go for myself and as Jess says staying with the panic until it decreases, and not moving on to the next step until you can do the previous step easily. My first aim was to get out of my bedroom and in to the next room. Such a small step, but a huge one for me. I continued doing this until I felt ready to move on to the next step.
Another thing I do is look at a situation and give it a mark out of ten for how much anxiety it is going to possibly cause. If its a 3 out of 10 I make myself give it a go, if it's 9 out of 10 I opt out.
I wish you well in your recovery.