Someone changed how we count years, so you are only in your 6th year after you enter the 7th.
What changed? If you had a son born on November 15, 2013 and someone asked you today, "How old is your son?" Would you answer "My son is 5 years old." Or, "My son is 6 years old." If you are calling him 6 years old when his 6th birthday is still 9 months away, then something is wrong.