Beginner Yoga...Is There A Pre-Beginner Available?!?

So I got ambitious and tried yoga for the first time this morning. Ummmmmm....is there a pre-beginner version, cause I was struggling?!? I felt like I looked eerily similar to the cat in this photo below.

I'm determined to keep at it though. Maybe someday I'll actually be able to get my heels flat in that downward dog pose, (it wasn't pretty, actually quite ugly). I've got 40lbs to lose, although I'd be happy with 30, and I hope that I'll be a lighter, healthier version of me by 2013.