What is this "thing" that keeps happening? Help me understand.

Feeling a bit dumb but I don't know what this is.

For reference, Level 94 Oracle werewolf/wyvern druid...

10 times or so since I've started maps this "thing" has happened and I can't piece together what it is or what's triggering it.... I think it happens after pouncing and I hear a werewolf howl THEN there's this symbol that appears above my character, it's red, and it flashes very fast, maybe half a second while the screen darkens a bit similar to activating lunar blessing and then immediately goes back to normal... it happens so quickly that I can't make out what the symbol is. It's so rare that I can't figure out what's triggering it or what ittl means....

Does this sound familiar?