Why does heart focus cause intense anxiety and labored breathing?

Jaise hi dil pe focus karta hoon, mujhe tez anxiety aur ghabraahat hone lagti hai, aur lagta hai jaise saans phool rahi ho. My name is Ravi, born on 5th May 1991. Time: 7:45 AM. Location: Indore. Yeh feeling bahut uncomfortable hai aur stress deti hai.