I could have ignored the feeling and just got on with that, but I believe that it's just as unhealthy to deny the feeling as it is to panic. Sure, the panic didn't help me at all, but feeling the emotion, acknowledging it and letting myself be upset for a day really did help. I felt it, I dealt with it and now it's gone. I don't have the undercurrent of fear running through me, hidden beneath the surface, it's gone because I dealt with it.
So many times we don't allow ourselves to feel a certain way because "there's always someone worse off than me" and that's true. It's also true that this is our life and whilst others may be suffering more, this is our reality. It's okay to be upset/angry/hurt/scared etc. It's your reality, don't deny yourself the opportunity to feel whatever you need to feel.
I posted a while ago about my Crohn's being back and me panicking for a day. Whilst I'm fully aware that panicking does no good, I believe that sometimes it's good to feel the emotion. And that's what I did. I allowed myself a day to panic. I acknowledged how scared and worried I was, I lived with that feeling for a day and then I pulled myself together and got on with the task of getting better.