So 4 months ago I bought a 2012 Volvo S60 t5, with about 85,000 miles on it. Drove like a dream, I had my mechanic friend check it out before I bought it and it looked good, the maintenance records are really clean, the previous owners took really good care of it. Round a month and a half two months ago, I went and got the brakes done, and even though I know how to change my own oil while I was there I just decided to go ahead and get the oil change. Thing is, my mechanic didn't really tell me but they aren't familiar with European cars that much. And not even a day after the oil change I started to hear like this weird kind of knocking and rattling sound, I can't really tell the difference to be honest. But it happened while I was at work so once I got home I noticed that it was having trouble accelerating too. And I don't really know anything about cars, this is the first car I've ever bought, but I know that this isn't good lol. I tried checking what I could using the internet and whatnot, but hoping you smart people could help me at least diagnose the issue so I can see if I need to sell a kidney for an engine replacement or not 😂😅. I don't know anything about Volvos let alone cars, I was just told that they're fun to drive and reliable for the most part and are built like tanks. Video attached below. Please help me. 

Volvo s60 2012 t5 engine diagnosis.