Stacie,
Everything you're describing is normal and just part of having this done when you're older. I had mine taken out when I was 28 and it took me 2 weeks before I was up and around again, and another week before I could eat anything substantial. Everyone says "Oh you're so lucky! You'll get to live off of a diet of ice cream and milkshakes!" WRONG!! It didn't matter what I ate or drank - Hot drinks, cold drinks, ice cream, mashed potatoes, refried beans - it all felt like daggers stabbing my throat!! I went from 118 lbs to 109 lbs in those few weeks.
One thing I would like to mention: Be careful what you feed her when she is finally able to eat. Remember that her stomach is used to meds and not a lot of nourishment, and she might not be able to keep some foods down if they're too heavy. I stayed with my parents those three weeks while I recuperated and my Mom made me scrambled eggs as my first meal. I think the butter she used in them was too heavy for my stomach and I couldn't keep it down. And that, as you know, is not good for the sutures.
I'd also suggest calling her ENT to see if she can take something for her congestion.
Good luck! I feel for your daughter. As others have said, childbirth was nothing compared to my tonsillectomy!
J.