Dent in my self-esteem

Yesterday was my last day as a long term sub. For the past six school days (the schools are on a six day cycle and I would see my students once every six school days), I had been telling my students goodbye. One of those days I was talking to the students as they were standing in line waiting for their teacher to retrieve them. A third grade girl and 5 or 6 of her buddies asked me how old I am. I would not tell them at first. So they began guessing my age. I felt I had to tell them that I am 33 when they started guessing that I was in my 40s and them moved on to guessing that I was in my 50s. Just a small dent in my self-esteem. No biggie!