Paranoia?

After receiving bad customer service so many times I'm paranoid when things seem to go too smoothly.

I had to revise our rental car reservation for our trip to Spring Training because we're flying into a different airport and arriving earlier than the original reservation. I called the local number I received from the baseball teams destinations package group, they asked my name, when I'd be arriving and to what airport, told me it would be $X more and that I was all set...

It was probably less than 1 minute on the phone!

I am a little worried we'll get there and not have a rental car. I guess it's not a huge deal, like they'd be out of rental cars and if our reservation wasn't there I could just call this number again. We should get all our reservation materials in the mail a couple weeks before the trip so I'll just check it then, but isn't it weird how rather than relieved the ease makes me more worried??