Will let the pro's touch on the finer points. And most of what I am about to say has already been mentioned.
1. Your x step is rough and appears very off balanced. It should be smooth and natural.
2. You need to pull through on a straight line. The general notion is to think of it as starting a lawn mower. You start slowly when pulling the cord and when you reach a certain point you accelerate. So, you reach back, bring the disc to your chest on a straight line then begin to accelerate towards the target while maintaining the straight line. Your footwork and body/core should move around the disk to keep the initial line to the target.
3. Your plant foot does not appear to be pivoting at all. It's very flat footed. The preferred method is to pivot on your heel to allow your body to clear out of the way and keep your line (see above) and then finish on the ball of your foot as you rotate through to finish.
4. It looks to me that you are really strong arming the crap out of the shot. By this I mean you are trying to generate power and distance by pure arm strength. It's very important to understand that more distance will be attained through proper, SMOOTH form. It is also very important to note that (at least from what I saw) you are swooping when you throw (similar to how most folks throw a frisbee). To throw a Disc in DG you want to reach back on a straight line.....slowly pull to your chest and then accelerate through while moving your body out of the way via the heel pivot. (Sounding like a broken record here, I know).
There ae a few other things but they are more detailed and I will let the more experienced folks touch on those as I don't want to give any bad information. The oe thing I want to stress is not to get frustrated and give up. This is an AMAZING game and it honestly will not take that long to get to a level where you can actually become competative (if that's your desire).
Watch the TON of instructional videos on Youtube....these forums have links to just about all of them.
It might behoove you to throw just a putter and maybe a mid until your form is where it needs to be. This is referred to as "discing down" and helped me immensely when I stated. Best of luck to you!