I used to have heart palpitations, but recently it...

Treatment of panic attacks:
There are many pharmacological and behavioral treatments used in panic attacks, including behavioral psychotherapy, which is considered effective in many cases. Regarding pharmacological treatment, you can use  antidepressants such as paroxetine 20mg one pill per day and it is a long-term treatment, some sedatives such as albrazolam can be used breathing into bag during the attack is also effective to wash carbon dioxide out of the body. It is also advised to get tnogh rest and sleep daily, and avoid stress and anxiety as much as possible, and exercise on a daily basis because it expels negative energy from the body. Eat a healthy diet which contains vitamins and drink sufficient quantities of water, as they help to improve the general mood.
Diagnosis:
Physical examination and knowing your medical history by the doctor.  Run some blood tests such as CBC to exclude anemia. Electrocardiogram (ECG), in addition to doing a psychological evaluation by the psychiatrist.
Symptoms of panic attack:

• Feeling of fear and death
• Shortness of breath
• heart palpitations
• Hyperhidrosis
• Headache
• Vertigo or dizziness
• Nausea and vomiting
• Tremor and the limbs
• Pain in the chest and abdomen
• Feeling tingling or tingling

Recommendation:
It's recommended to visit your family doctor for further assessment of your condition.