Can Anxiety and panic attacks happen over a period of time like a week or do they happen quickly?

I have all the symptoms of a panic attack or anxiety attack but I’ve never had them all at the same time I’ve had them all in the last week or so, I’ve had heart palpitations for months now and hot flashes and chills and random sweating for like a week.
I’m 14 if that helps

A panic attack wouldn’t last a week. But your anxiety can follow you everywhere and will not necessarily "happen" more so, be "happening" all the time.