Accidentally leveled my PVP character

I was doing some battlegrounds, not realizing that my xp bar was almost full. I was in a WG match at level 29 and when it ended it leveled me too 30. I was furious, It was probably one of my most fun chars too play on. I left a ticket and they said they could not roll me back 939 XP! That made me even more furious. So now im making this post too see if i can get some help. PLEASE!