Lobectomy

I was the same, petrified before my operation (had my right lung removed in 2014) especially as I'd never been in hospital before and the worst thing I'd had was a tooth out. I recovered very quickly (operation Tuesday and home Sunday despite a minor delay during the week) and I would suggest following any instructions you're given regarding exercise, medication etc. during your recovery. I went from not much to walking up to 6 miles on the flat within a month to 6 weeks. Listen to your body and don't overdo things but don't wrap yourself in cotton wool as you do need to move about and build up exercise for the best recovery. Although uncomfortable I found pain entirely manageable with medication given for it.

I'm sure you'll be just fine and afterwards will wonder what all the fear was for. Surgery is the best treatment you can get if offered.