Hey Jenn,
Flying is fun!!!!

It's the closest thing to being a bird that you can do. Can you think about being away for three weeks like it's a vacation or an adventure?
Only you know your limits. Respect them. I do know that when I forced myself to do things in the past that were past what my anxiety/panic limits were, I had a huge disaster on my hands.
Let me know what you decide.
Love and hugs,
Jan