Data usage not adding up

Hello and help.

I turned my laptop on today and connected it to my home internet for the first time in a few days.

Within 2 hours, I was out of internet and so confused as to what device was doing it, but when I checked my data usage stats, I saw the steam download, which I was doing, but the total data usage doesn't add up at all, over 155 GB.

I fear my laptop has a virus? please help ;_;

Image: https://postimg.cc/McdMS3Vx