Don't worry about it, its the easiest of all the test "we" go thru.
I did it on Monday....swallowed the camera at 9:00 a.m. and 3.5 hours later it was out. That is obviously really fast and not the norm. Most people it takes 8-12 hrs and as much as 3-5 days. The pill is no larger than a large multi-vitamin. You will have a belt with 6 electrobes stuck to your chest/abdomin. The worst part is pulling off those darn electrobes (they use some sort of crazy glue to make them stick) and then the strange looks; my wife and I went to the mall and I got looks from people like I might be carrying a bomb. You also can't eat or drink for a few hours which always sucks.....other than that its no big deal.
My doc said not to worry about it getting stuck....yes it happens and is a possibility but is extremely rare. And those individuals would probably have needed surgery anyways to clear the problem. Maybe she was just telling me that to make me feel better....I don't know.
Either way it was no big deal for me!!