Love in the Time of Melancholy

I've been in a sort of disconnected mood today. I thought my usual coffee would set me back on my axis but it only seemed to emphasize a tightness in my left shoulder and neck. I didn't know what exactly the mood I was in consisted of until some songs started playing on my I-tunes. There were a few that caught me by surprise, as I hadn't listened to them in a long time, and when they made their way through my head, flicking nerves that have been subdued, I sort of became agitated.
They were feelings of "what if's, what was, what happened?"
I'm reasonably young and yet I'm operating day to day in a life that many of my peers have yet to even really fathom. A life of marriage, of child, of futures to be secured instead of presents to be taken for granted. While I love it, although I wouldn't really change a thing there are days, like today, when I find myself a tad melancholy over days that I have missed, or rather, days that were cut insanely short.
My carefree independent days lasted from the time I turned 17 (March 2005) to the time I discovered I was with child (August 2007). Two years. Two years to enjoy a car purchased with my hard earned money, enjoy a new boyfriend, shop carelessly with the aforementioned hard earned money, give gifts carelessly ("oh, I was just at Urban and this sheet set reminded me of you so...here you go!"), take myself out on afternoon strolls, music to my ears, wait for new boyfriend to get out of his classes, afternoon delight, no need to focus, no need to plan.
I envy everybody's "newness". Newness of experiences. I feel like I have lived a few (hundred) lives since I took off my cap and gown. My pages yellowing out. I feel as if the air smells differently, the buildings seem shorter and though I can still do some of the things I used to bewitch myself with it isn't the same. I just can't seem to catch it. But there it lingers, fluttering in front of me like an ethereal ghost and I look down at my hands to find bronze dust flaking off my fingertips.
I don't want to sound too emotional, unthankful for the present, regretful, because there are rarely any regrets in my life, I just wonder what I would feel like now if those years had lasted a little longer. Perhaps like more of an adult? Who knows. I wonder though, if anybody else ever feels this? Maybe I'm just ready to shed my skin again.