When is fearing people blameworthy or praiseworthy in Islam, and does a rapid heartbeat indicate weakness or cowardice, and what is the solution to overcome that?

Fear is divided into two categories: natural, innate fear, which is not blameworthy in Islamic law, such as fear of darkness or predatory animals. The second category is blameworthy in Islamic law, which is submission, abasement, and believing that the object of fear possesses harm and benefit. This is polytheism (shirk) and is not permissible for anyone but Allah Almighty. The remedy for fear is to rely on Allah and put one's trust in Him, and to believe in divine decree (qadar) — that what has befallen a person was not meant to miss him, and what has missed him was not meant to befall him.