The first time I played anything other then at my local rental site was early 2008, can't remember the exact month but would probably have been February or March, shortly after I turned 18.
I hadn't ever played with my own kit, had only actually had it a couple of days, and found myself playing NSPL Division 2 with a team comprised of older players using mainly mech markers but I think with one pump in there.
Despite never having played before, or even put a single ball through my marker before that day, I ended up playing front, was absolutely terrible but had an amazing time. The team somehow ended up winning the division despite my best efforts and I still remember that the guys let me take the trophy home, and it still has a place in my trophy cabinet alongside all of my archery trophies from previous years.
Unfortunately since then I've never been able to play for long, every time I have the money to get back into the sport I play for a couple of months, then something major inevitably goes wrong, and I'm forced to sell off my kit again. Has happened 3 or 4 times and is incredibly annoying, hopefully I'll be able to get back into it properly for next year though.