DCmay, I hope you can see how many folks have crowd and anxiety issues but still love the MK. I'm one of those who also have anxiety issues with crowds. I enjoy the MK but know when I've had enough and need a break. One thing you can do is take one of the resort launches and cruise your way to the various MK resorts....get off at one and look around, have a snack and just recharge before heading back. My personal favorite is the Wilderness Lodge but lots of folks love the Polynesian.
Take it slow and enjoy...