Brain fog and Headache back right side and top of head with occasional tingling on top of head during day for 4 weeks. Told it was due to anxiet. Ok?

May not be anxiety. Anxiety can produce tension headache and difficulty concentrating ("brain fog"). But, if headache continues in location you describe for 4 weeks, it is possibly something more serious. Please consult your doctor, or a neurologist. They can recommend an MRI, EEG, or brain scan to rule out any serious issue. If all tests negative, consider CBT psychotherapy to treat your anxiety. Get help please.