OK, let's fix your little red wagon.
First thing is that you feeling slow on the third pull is starting all the way back in how you move from first to second pull. Immediately as the bar passes your knees, your knees are moving forward - it looks like you're trying too early to push up with the legs. You need to stay over the bar and keep the knees back a bit longer. I see that you're trying to wait to explode high, but you're shifting your position before that point. Keep extending the knees until the bar is at mid-thigh, at which point your shoulders should still be in front of the bar at least a little. Don't even think about exploding at the hips before then. As the bar passes mid-thigh, then snap the hips and punch the legs together. Basically you need to make that explosion... more explosive. The best way to do that is to make it more abrupt by waiting longer, which will put you in a much better position for speed and will bring the bar into the hips better.
I would do lots of high-hang snatches - bar starts at upper thigh - focusing on snapping open/up and pulling down as all one movement. Also halting snatch deadlifts, stopping with the bar all the way to the hips with the shoulders still in front of it. In this position, you should feel good tension on the hamstrings. Doing a halting snatch DL + high-hang snatch (aka segment snatch) + a snatch once you've done some groundwork with the first two exercises can help also.
Next, you're a bit tense in the arm region during the second pull. Focus on engaging the back into a rock solid arch, and using the lats to both reinforce that arch and push the bar back into the body. But the arms themselves need to be relaxed. Only when the bar comes into the hips as the hips explode open do the arms engage to pull you down. Being tight prior to that will usually slow the transition down. If being conscious of it isn't adequate to fix it, try doing some snatches with straps to allow you to relax your grip a bit which should help relax the arms.
Your pull under itself could be cleaned up a bit as well. First is the way your feet move - you're sweeping your toes back rather than moving the feet only to the sides. Punch the heels down into the floor right away, and think of lifting the knees instead of lifting the feet - that should help keep your feet under you/the bar. And you just need to get them back on the floor faster.
You need to be more aggressive pulling down - pull the elbows up and out as hard as possible - you need to think of accelerating down, not just moving down. Also I would suggest that you try getting lower under the bar at the point you lock it out. I know you've heard me say a million times that you have to meet the bar and ride it down, but that just means you need to stay connected to it and always be where you need to be - if you focus on pulling down and receiving a bit lower, it will probably also help w the arm pulling and floating because you won't be so focused on moving up. You're looking for an abrupt jerk on the bar at the hips, then move down immediately. No more power snatches for a while until you're getting under the bar faster. Try some tall snatches when you warm up - really focus on being aggressive pulling the elbows up and out, then turn and punch hard. Get low.
And with all that being said, remember 2 things: 1, you're not doing bad at all, particularly considering you're doing all this without coaching and 2, welcome to weightlifting: you're going to go through periods of time when you feel like you've forgotten how to do everything and there is no hope at all for you. I promise you'll move past it - but the more frustrated you let yourself get, the worse it will be.