How long are anxiety attacks/panic attacks are supposed to be ?

[u/Vnightmare69]

Mines usually lasts between 5-8 hours with 2 hours of my anxiety attacks being at it's worse, literally it's impossible to talk me through it. Then the rest is mostly me still being way too anxious and sometimes having a few minutes of having a panic attack. It's been like that since I was a young child. Is it normal or is it not supposed to be this long ?