Weird fps drops

Greetings everyone.
Something weird started happening today around ~5:00pm server time. The servers went down and when they came up I went back to leveling my alt and I had weird FPS drops. I usually play with 60 fps constantly but now when i entered i got my fps reduced by half, down to 30, sometimes even lower.
I'm wondering if i'm the only one with the same issue? Is there something I can do?
Could it have anything with the windows updates? Since i havent done them in a while, downloading them atm while i'm writing this.
Could it be something on the server's side?

Thanks in advance for your answers.