Yoga for dummies?

I like to think I'm fairly "good" at yoga, although a devout yogi would shake their head disapprovingly at the use of this word. You're supposed to allow your body to do what it can and be happy with that, and not compare yourself to others, yada yada yada, which is part of the appeal for me, but if you're falling over all the time you can't help felling like you're "bad" at yoga. And I'm not falling over all the time, generally feel like I have all my body parts in the place they're supposed to be in, and I can do a headstand no problem. So I think I'm pretty "good". That is until last night. Hatha 2. Not for beginners. I was falling over. A lot. It's always good to be humbled. It was a night of twisting postures, and this and this are no easy feat. They may not look too hard, but when you're twisted around like that your balance is all off. And my poor hamstrings. Will they ever become more flexible?