I only call them flashbacks when I'm lying on the ground and talking to people who aren't here, but I know my T also calls less severe things flashbacks. (For example, when I only feel as though the event is happening again, but I still know where I am)

I usually call what you describe "being totally overwhelmed, paralyzed and suffocating under the memories, thoughts, and feelings". Not sure whether it's technically a flashback, but I think it's worse. I know how to fight flashbacks, and they're familiar, but this? Not nice.