Wow, that's awesome. Congratulations!!!

I will tell you that when I started my job, 4 years ago, the same thing happened to me. I was 18 and had been there only a couple months and was promoted to ass. manager. There was 1 girl who had been there for 6 months longer then me and she wanted that job. She was in her 40's and hated that an 18 year old got the job that she wanted. She snubbed me everyday there on, she was always mean to me. I did my best to kill her with kindness. She ended up getting fired for not being a "team player".