I am acutely aware I may be overly paranoid here.
I left my laptop unattended by myself (I trusted a friend who was beside it). He assures me it was not touched. When I returned I was still logged in. When the network went down shortly later I was clicking through my connections and found my ethernet connection (which I never use, and was unplugged before and after) had last been in use 40 minutes earlier (while I left it unattended). This ethernet port "unfolds" from the laptop and was unfolded (could have been when I took it out of my bag) which is unusual, I did not consciously open it. At that point the network was stable (and is wifi), I took a look in the auth logs but have no idea how to get time stamps or even where I could look to see if something was used. At least I am sure no sudo attempts were made/failed.
Should I be worried/go and speak to security? There is video surveillance there which is my next stop when I am more certain.
Any advice would be appreciated.