Swimmer...cyclist...runner...triathlete?

Hi!  I'm new to the site, and new to the sport.  I swam competitively in high school ( a long, long time ago), I used to race mountain bikes ( a long time ago), and I've done a few 5k's, 10k's, and half-marathons (not too long ago).  I was training for a full marathon this November, and was goaded into doing a Sprint tri by a friend, just to break up the mundane routine of running, running, and more running.  Unfortunately, I sprained my knee at work, which landed me on the couch for a few weeks.  

But I have decided to nix the marathon, and train for the tri instead.  I've been thinking of doing a tri for a few years now, but life always seems to get in the way.  Well, I'm not waiting any longer!!!  Lol! 

It's in October, and it's gonna be my first Sprint.  I'm stoked!!! And freaked out!!