Ok, so I installed 'Tenda's' (the adapters company) crappy little utility, and I realised that when I opened a game and was pinging servers it game "Retry Errors". Although I have no idea what that means.
The "Retry Error" was bouncing up very quick. A couple of seconds after the printsrc, it was at 155.
My computer is in my bedroom, I would have to have a VERY long ethernet cable all the way up the stairs and into my room. Trust me, if it was a possibility, I would do it without a doubt.
You're dealing with WiFi, it uses unlicensed spectrum which is prone to other devices abusing it, and problems from microwaves. Maybe it could've been something else entirely - but you'd need to figure out how to debug it yourself.