The law can be subjective. What's really the determination is first the DA and then a jury. It's not always whether you feel your life is in imminent danger, it's whether a DA and jury will agree with you.
A potential a$$ whipping is not necessarily an imminent danger to your life. Your loss of pride, while humiliating, is never an imminent danger to your life. For most people, a broken arm doesn't put your life in imminent danger. TN courts have already held a broken nose does not put your life in imminent danger and does not justify the use of deadly force. Then there's other factors as well, your age, sex, and health and physical strength versus that of your attackers.
Bottom line, your panic doesn't necessarily prove you right by TN law. Before I pulled my gun and had to shoot someone who just wanted to fight and who appeared to be unarmed, I'd want plenty of my blood and bruises to justify my actions.
For the most part, Georgia (where I'm from) has better carry laws in this situation and also in property defense situations (you can use deadly force to protect property in Georgia).