I think I'm old...

Normally at my age people are out clubbing, dating or having fun on weekends, I do envy them who can pull it off every weekend, however for me.. I can't do it.
I've been old ever since I was 15 yrs old I think. ^^
I do drink and I like to go clubbing every now and then.. and of course having fun.
But lately I'm so tired and exhaused and have no strength to go out, put excessive amount of make-up on etc. I rather stay at home, sleeping, read books, watching movies, go to the gym etc. As you can see do things by myself, however I have to admit it, I do enjoy it ^^