I also had a tonselectomy at the age of 20. I am now 43. It took about 2-3 weeks for me to completely recover. I was tired for awhile afterwards, but 10 years ago I was diagnosed with Fibromyalgia, and have had it in my system since I was born. I think that is probably why it took me so long to recover. My voice did not change at all that I noticed. Good luck!