Hi there ~
It seems like you know that you have panic attacks. If you have had a recent ECG and it was normal, I would suggest that you consult a psychiatrist
who can help you with medications. SSRIs along with short term benzodiazepines are helpful. You may need to be on them for a while to experience benefit. It is also suggested that you practice relaxation techniques
, deep breathing exercises and physical exercise to gain maximum benefit. Adjuvant psychotherapy
or counseling may also be helpful. Sleep difficulty is common and treating the panic attack and associated anxiety
should help with insomnia
I hope this helps. Take care.