iPhone 4s and hotspot data usage

I'm in a temporary situation where I have an iPhone 4s, AT&T cellular hotspot and Apple TV. I have unlimited data plane on my iPhone but only 5Gb on the hotspot. If I airplay using my iPhone connected to the hotspot for the network connection required between the ATV and iPhone will I be using the hotspot data or the iPhone data plan? Is there a way to turn off the hotspot cellular leaving the hotspot acting strictly like a router? Bottom line is I want to use my iPhone data plan to stream video and not use up the hotspot data. Thanks in advance for your help.

Kelly

P.S. My iphone carrier will not let me turn the iPhone into a hotspot...