I know how you feel, I hate being boxed in. I always try to remember not to pull up to close the the car ahead of me just in case I need to cut the wheel and punch it. It good to be aware but it doesn't sound healthy that your hands were trembling. I probably should be a little more worried about some situations but from my view you shouldn't be that worried about this situation. Don't get me wrong I carry a knife, flashlight and my 9mm everywhere I go and I am constantly looking around. I have always picked the safe spot in restaurants and I keep in mind my "duck and cover"/escape routes where ever I'm at but I myself wouldn't get the shakes in that situation. Again please don't take it as me slamming you because its better to by hyper vigilant than hypo. But just make sure your not causing yourself avoidable negativity.
So what is your routine when you leave base. I'm not familiar with that life style. Do you usually swing by your residence and grab your pistol so you can cc off base?
I appreciate the reminder to keep up the SA and avoid boxing myself in when possible.