FORT JACKSON, S.C. -- I never worried much about getting old. Despite the stereotype that women constantly worry about their ages - and subsequently began lying about it - even as I neared my 30th birthday, I never gave a thought that I was old.

Maybe it's because my husband has looked about 18 since we met eight years ago, and I feel young by proxy. Or maybe it's because I just never imagined that I could be considered old, despite having been called, "Ma'am" on and off since I was about 17.

Regardless, I thought of myself as young, and that's all that mattered.

But a couple of weeks ago, I think it finally started to set in that I'm not a kid anymore.
My husband and I drove to Tallahassee, Fla., for our alma mater's homecoming football weekend. Saturday morning, we woke up fairly early to watch the annual parade. That afternoon, we attended the football game, cheering our team on to victory in the hot sun to nearly 7 p.m. By that time on any other weekend, I'd already taken at least one nap.

We miraculously managed to secure a babysitter, and we made plans to go to a party that night. At around 8:30 p.m., the baby fell asleep. Shortly thereafter, I realized I wanted to sleep, too, but there was no time. We were supposed to meet for the party at 11 p.m., and by that time I'd started watching a marathon of one of my favorite shows on a channel I don't get at home. I actually thought about calling off the party plans - saying it was because the baby was already asleep - and curling up in bed to watch my favorite show.

I went to the party, but was secretly overjoyed that pretty much everything in Tallahassee shuts down at 2 a.m., meaning I would not be expected to stay out all night.

I wonder at what point the transition occurred that makes staying home, lying on the couch watching TV sound like more fun than hanging out with friends. And why is it that my internal sleep clock kicks in earlier and earlier, making staying up past 9 p.m. an increasingly difficult battle.

It's not that I have ever been much of a partier, but even when my husband and I have our movie nights; one of us usually falls asleep before the movie has even reached its midpoint. And when a friend suggested attending a spoken word event for a Tuesday night outing, I grimaced when I saw the time - 9 p.m. - and thought to myself: "On a weekday'"

Am I saying that now that I am a mother, I can't go out and have fun' No. But maybe I should remember that with my increased responsibilities being a wife, mother and working full-time, sleep is an ever-decreasing commodity that I need to conserve.

Last weekend, a group of girlfriends and I traveled to Las Vegas to celebrate my 30th birthday. And for that weekend, my motto was "I'll sleep on the plane." I stayed up late, woke up early and didn't look at my watch the whole time. The funny part is I didn't even feel sleepy.

That trip, I suppose, was my final hurrah - the transition into "real" adulthood.
And now that I've reached that pinnacle, I still don't think I'm "old," just wise enough to know when to call it a night - even if that means going to sleep before "Grey's Anatomy" comes on.