I have a great experience with this and I was searching for many years the 'right' supplement to raise this 'fight' over 'flight'. I was in such a bad situations (like meeting, presentations... ) that I had to leave the room, with extremely strong heart beat and panic. I had this feeling like 'I will start to cry' and the heat was coming to my head (red flashes and sweating). From time to time I was so obsessed that this bad feeling will come back that I was experiencing troubles in day to day life (in the shopping, talking to the people, parties...) I completely lost the confidence and had insomnia. It was terrible but I never visited doctor. First I tried things like bromazepam but that was not something for daily use and my brain was slow after this so I decided to rely on something natural. I also tried the famous Phenibut.. that thing still scares me and I haven't touch it for the past 1 year. Sometimes it gave me this nice feeling but sometimes 'strange' feeling, and there was a strong potential to become addicted to this stuff.
I tried l-theanine, kava-kava, brahmi, rhodiola, valerian, noopept, panax ginseng, schizandra, holy basil...nothing helped or helped first few days (like valerian).
I was desperate but I was still looking for something that will 'bring me back to my normal state ', something that will make me feel confident like before, without any fear and worries.
Then I found adaptogen herb ASHWAGANDHA (also called indian ginseng) and this thing really changed my life. I've been using this for the past few years without any breaks, I take only extract form. Its hard to say how i feel, but I can only say that ALL bad feelings disappeared and I feel 'protected' when I take it. There is no need to 'flight', just 'fight'
So my answer to this is try ashwagandha, it has been my life saver. You cannot be sure that you will have the same benefits but it's worth trying.
It's possible to experience headaches first one week after taking but this will go away. Its also good to take it before bed for the first 2 weeks (you can expect strong, deep sleep).
The best extract on the market is called KSM-66, there are some brands that are using this like this one: http://bit.ly/1SPUKaj
You can also try other adaptogen herbs like Rhodiola.. but for me ashwagandha is the one that really changes the way I will. I'm talking about dramatic changes.