Entire dragon fight is broken on Xbox and PC.

Went to go kill the Ender Dragon yesterday and when I was doing the fight the dragons breath would be completely invisible and would stayed around for roughly 5 mins (alot longer than usual), the health bar also completely vanished on me and I got absolutely no XP, these bugs completely break the dragon fight and made something that was extremely easy for me extremely hard and irritating. I like a challenge but I don't like doing one that's bugged out like this. I died nearly 15 times due to the invisible dragons breath and lost all of my items waiting for it to disappear.