Hotspotting-Data DisappearingFast!

[Atmabindu]

Can anyone please tell me if this is normal. I hotspot Ted my laptop via my samsung smartphone and it used 500 gb of data in two or three minutes of streaming a video(educational speaking only, no complex visuals)!!? I don't believe this much data could be sucked up so quickly. I won't be Hotspotting-Data again if this is the case! I'm sure it took an hour or so for this much data to be used last time I hotspotTed my laptop via my s7....Anybody give me an idea if Telstra are ripping me off??!!*Well of course they are - but more than usual?) Thanks! Kate