Welcome to HCM
Your problem definitely is panic attacks. You must believe your doctor or find a doctor whom you can believe. Get yourself checked up thoroughly and once found that you are alright, then believe it.
Secondly, panic attack shows all the symptoms you mentioned here. But every person who suffers seldom believe that they have anxiety
and panic attacks. Consult a psychologist
and get well soon. I can help you if you desire so.