What Went Wrong?

I to tryed to start my Happy Holiday Fudge making today,like I have now for atleast 5yrs.(before i only made cookies and cakes)I was very excited to taste my way to the finish line.I checked the ol' candy therm.it worked good,measured out everything, I even went as far as to make sure my bladder was empty!LOL.I began to warm the milk ,sugar and butter.The smell began to take me back to my childhood in the kitchen with my Grandmother.I can see use in the kitchen talking and having fun.I always made candies and fudge with her,She was the Best cook I ever had the Honar of knowing.Well I wont go down that memory lane I told myself.So I stirred until The temp reached 212.I know ladies ,that is the wrong temp, but I failed to mention that the mixture had been boiling for close to 12 min. I knew I should have stopped the process, but I knew that I had checked the therm,before I began and it WORKED.So to make this very long story short....It was awful awful awful.I checked that silly thing in boiling water like everyone else that makes candy and it worked.To my horror , I didn't get to taste anything and ruined all those pricey ingr..I hope to have some Christmas Luck tonight.I am so nervous to waste anymore stuff,I just wish I new that this other therm.will work ..So MERRY CHRISTMAS LADIES,and I PRAY YOU HAVE ALL YOU NEED THIS SEASON.