The video has issues that mostly related to lack of adjusting prior to recording. I think, most of what you are seeing is common by way of poor setup.
To begin with, at the end of yawing the a/c you see blurred images that come into focus. This is actually something that should not be happening, but does or several P3's. I have not researched what is the actual problem that is taking place. I just know from experience that if you slow down the Yaw settings it will help and usually eliminate most of that issue. Your a/c appears to be set at the current app's default setting which is 150 in the Yaw function. Slow this down to 110 or 100 and see if you are still comfortable flying the a/c. It will help remove a lot of the jerkiness it now clearly has.
Next issue is the video settings are in dire need of adjustment. Just addressing a few things will make great improvements. Rather then giving you numbers to use, ect...there is two basic things you really should do which do not take that much time. One of them is to read and understand what and how to use the iso setting. The other and probably more important is the Histogram function. You only need to find and read a basic description about it. Just know that Black is Dark, White is Bright, and adjust for a pyramid in the middle. Without using a lens filter I tend to move the pyramid towards the darker side a click or two. You'll know exactly what I'm referring to after reading and adjusting your 1st time. There is nice rewards in using the histogram tool each time you record or take a pic. Btw, in your video look at the close up of your face or the white dog and take notice of how over exposed the two were. A couple of clicks on the rightside thumb wheel would have cleaned a lot of that up.
The last thing hurting your video is youtube. I use it for 90% of my of video. But it robs your video and audio quality a lot. If you haven't already, get your account setup on skypixel.com. You set the video to be viewed at 720p and 1080p but try to stay away from the 1080p as it will only hurt those viewing it publicly.
.....and Good Luck.