Yea, didn't look too bad. One thing to get more height, other than just trying to push off harder, is to throw your arms up more. The motion is similar to having your arms down but forearms pointing up and extending them out above your head. You might want to try this technique on a trampoline or something first though... I remember the first time I did it, I threw them up right but didn't keep the technique for the rest of my body and under-rotated a lot.
Another thing that has helped me get more height on mine is to imagine a wall in front of me that I need to dive over. This helps me to get my chest/torso up really high and then tucking instead of just throwing down into a front.
EDIT: And another thing, yea, don't spend too long and get frustrated. Just work on it and if you don't think you are improving anymore, just stop. Try again the next day. I know that this break from practicing the movement has actually helped me a lot in getting techniques down. You can go and think about your technique and watch other people do them too.
