It's easy to feel old when looking at the SDN board (which is one reason I also visit the Old Pre Meds board, where I can feel young!) I find it helpful to think of myself as a grownup rather than an old lady. Look at some of the more contentious threads here about osteopathic vs. allopathic, my school is better than your school, my way of studying for the MCAT is cooler than your way, etc. Though there are mostly fine people here, and a delight to correspond with, a few of the threads here and there will remind you to see your maturity as the asset that it is.
I suspect that as I walk this road, a lot of people are going to have something to say about my age. Including me, sometimes. Most people will even mean well. I'm hoping to think it's funny, as often as possible.