Nintendo Switch

i just beat the Ender dragon for the first time. Died 3-4 times in the process. Finally killed it, it did the animation of exploding over the center platform. Showed the green orbs falling but they never hit the ground. I have gained no xp from the battle. Is there any way to receive the xp missed?  Kind of disheartening to put time into this, beat the boss and you give no reward... hard to get motivated to do anything else.