The only possible way for that to happen a fully PvE geared feral druid with a Mastery trinket proc, Tiger's Fury, full buff's and Berserker (the BG buff) up. Even then that's pretty high. You probably had a rip, rake and shred hit all around the same time and your add-on or combat log grouped them.
Other-wise, impossible scenario is impossible. People like you are the reason feral is being nerfed for no reason.