Esse “well done” corresponde a “Congrats” (parabéns); não é o nosso “bem feito” (no sentido pejorativo, que seria algo como “it serves you right”)
*fight back* = to defend yourself when someone attacks you or causes problems, and try to win or stop the situation.
“Brazil was losing by 2 goals at halftime, but fought back well and won the game.” “Don't just accept defeat; fight back!”
This phrasal verb can't be separated.
Source: Knights’ English