Hello, My heart is beating so fast suddenly and I...

Signs and symptoms of hyperstimulation of the sympathetic nervous system

Tachycardia: increase pulse rate
tachypnea : increase respiratory rate
Agitation
Excessive sweating
pupillary dilation
Mucsle rigidity

Paroxysmal sympathetic hyperactivity

is a syndrome that causes episodes of increased activity of the sympathetic nervous system. Hyperactivity of the sympathetic nervous system can manifest as
increased heart rate
increased respiration
increased blood pressure
diaphoresis
hyperthermia
flushing
dystonic posturing
pupillary dilation

Panic Attack Symptoms

Racing" heart
Feeling weak, faint, or dizzy
Tingling or numbness in the hands and fingers
Sense of terror, or impending doom or death
Feeling sweaty or having chills
Chest pains
Breathing difficulties
Feeling a loss of control

Advice

If you have recurrent attacks, you need to see a doctor