Bedrock Destroyed by tnt

I went to the end to fight the dragon, then I decided to do /fill ~ ~ ~ ~10 ~10 ~10 minecraft:tnt to place 900+ tnt. I lit it on fire to hurt the dragon, and it did hurt the dragon. also, the bedrock for the escape portal BROKE. also the closest tnt to the portal was 3 metres.
how to reproduce:
go to end
go to escape portal
type /fill ~ ~ ~ ~10 ~10 ~10 minecraft:tnt
the bedrock has exploded