It looks like you move pretty well and have a good sense of the technique. You're doing a good job keeping the bar close and staying over it during the first pull. In the second pull, you're lacking extension from the knees and the ankles so all the power is coming from the hips. Think about pushing against the floor with your legs as long as you can and getting that full extension. This may be the reason why you're jumping forward as well. I would suggest doing snatch/clean pulls to help.
Also, if your want to gain some overhead strength, do some presses/push presses and snatch presses/push presses behind the neck. You can do clean-grip overhead squats or squat jerks as a warm-up instead.
Additionally, I agree with Richard and Javier when they say you should have a coach with you that knows what they're talking about to help correct you as you train.