Hotspot for Sprint

Hello all,

I have an HTC Evo LTE from Sprint. I have installed the PDANet+ app that allows(supposedly) allows for a free hotspot connection to the internet on any given device like my Nexus 7. But when I activated this free hotspot, I get something in the notification bar that says that the Sprint hotspot is activated. Does that mean I'll still get charged since it says that its Sprint's hotspot? Or is it normal?

Also, will using this hotspot for like web surfing, and YouTube for two or so hour a day make me noticeable for data traffic? Thanks:-)