Default LTE Service but No Data/Calls

Hi Guys,

I'm on AT&T and love my new phone, but have run into several issues with data. I'm seeing that I have service (4 or 5 bars) and that it's LTE. However, when I try to load a webpage/google search etc. nothing works when I'm on LTE - it shows that a data transfer is attempting to happen but I never load a page or anything.

My battery stats page also seems to show no service except at a few key times. I've tried turning on airplane mode and then turning it off again and I've tried restarting my phone. Nothing seems to work.

Does this sound like a cooked S5?