I've had a ball python hatching so cold that it appeared dead. Mouth open, tongue hanging out, completely limp with no movement at all. I left it in a warm cage and came back later and it was acting just fine. Never had any further issues with him either. Best thing is to just keep an eye on him and let him settle into his new surroundings before doing much more with him.
Fed Ex where I live can be really bad depending on the driver. I've had packeges sent back to the sender before because I supposedly was not available for a signature (I had been sitting on the front porch all day waiting for the package) I'm sure the driver just didn't feel like driving all the way out to my place so he just skipped me and tried to put the blame on me. I've never had any problems with UPS though.