My iPad won't let me view the video unfortunately.
About the nippiness, it may just be that your sun is at a stage in his life where he is gonna become nippy. This can go on for a few months, but after that, hopefully, he should be fine. This is definitely not unusual, all birds go through this stage.
The only thing I can think of to stop this behaviour, is to not reinforce it. By this, I mean when he bites you, keep your hand there until he stops biting you and he will soon learn that biting you will not solve the problem. It will take a lot of pain, but hey, no pain no gain lol. Good luck!
Regards,
Laducockatiel
