A childhood belief about birthdays

I was born in 1998, but I originally thought I was born in 1999, because of a mistake my first grade teacher made. It was Chinese New Year of 2005, and I was currently 6, but I was about to turn 7 because my birthday is in April. My teacher was telling me and my classmates what animals we were in the Chinese zodiac, and she was unaware that I had not yet had my birthday that year, so she subtracted my current age (6) from the current year (2005), and therefore ended up with 1999. She thought I was a rabbit, but I am actually a tiger. She said she was a rabbit, and I find it a shame that she mistakenly thought she was the same animal as one of her students. Anyway, my mom was the one who eventually told me I was born in 1998, and I argued. So she had me subtract my age from the year. This time, it was after my birthday, so I subtracted 7 from 2005 and got 1998.