Actually anxiety can cause any kind of symptom, dizzyness and fatigue is some of the common one.
I have faced stress headache+migraine for multiple days earlier days of my anxiety problem, add that with dizzyness, damn terrible wei, thought kena stroke ooo.

but since you said your problem were due to stress, there is possibility that you might faced with mental illness.

last time used get headache, take Panadol or ibuprofen. then found out got high BP, so with medication headache also very less. lucky not stroke yet

so frequent headache, get checkup most probably other issues