If you're panicking, you are believing a lie of some sort. Finding out which lie it is will not dramatically affect the course you take: you have to slow down, pull yourself back under control, and quit believing it. Panic is a result of bad thought: and it is the moment you can't check other bad thoughts when you've succumbed to one bad thought. That is the idea behind "don't waste a good crisis". Some say that panic is the natural result of fear, which prepares your body for flight or fight, and should be harnessed. But records of people in danger prove that panic is the way to be killed or kill most of your party, not the way to save yourself or them.
Good rule of thumb: attack the person who says, "Fear this!"