What does this mean?

I'm 39 but I keep thinking I'm 20 years old. I keep seeing 20 year olds as my age and 30 somethings as older siblings even though they're my age. I also don't find most men who are only a couple years older as attractive to me they look too old for me in appearance. I see a 27 year old as more close to my age than a 40 year old. I'm also flirted with by 20 something's more often who get confused when I tell them my age and think I'm joking.

When I look in the mirror I also think I look 20. But it's not just me. Whenever I go somewhere they ask me for ID, I'm stopped at casinos, to buy lotto tickets, to go to a bar. I had people ask me if I use Botox or skin treatment I don't. I don't have a single fine line on my face. I went to a health clinic recently and when I put my birthdate 1983 they asked me at the desk if I meant to put 1993 not 1983, I said no and they said wow you could pass for a teenager what's your secret. This happens often.

What does it mean?