Yes, I always make sure I will not run out. I would panic if I did not have them with me at all times. I never know if I will have a panic attack and need them.
There is absolutely nothing wrong with asking for more. It's something you need, and your doctor is there to help you.
It's perfectly okay to ask the doctor for more Xanax if you feel it's helping you. Your doctor is the one person you can always, always be honest with.
Don't be scared to ask your doctor for more. If you need them, take them. Would you rather suffer?