Hello thanks for asking from HCM You have developed panic attacks since last one and half years and these were severe. Now you have headache, derealisation, depressive symptoms, dizziness, insomnia etc symptoms. Such symptoms are common complications after severe panic attacks. I would advise you to consult a psychiatrist immediately for such symptoms. Medicines like SSRIs as Fluoxetine, Paroxetine, Sertraline etc are commonly used in anxiety and panic attacks. These medicines will reduce the severe panic symptoms and will also help in improvement of depressive symptoms. Apart from this medicines like low dose benzodiazepines or beta blockers can be used in cases of severe panic attacks. Try relaxation exercises, yoga, meditation to keep yourself relaxed. Visit a psychiatrist for detailed prescription. Thanks, hope this helps you.