Everything is laggy

I just downloaded the game and when I got to the login screen it was super laggy. Then when I went to character creation it was working fine until I clicked Dk and it went back to being super laggy. I made a druid and now when I play it is super laggy even when I set the resolution down and the video settings to the bare minimum and my computer is a pretty good computer. What could be causing this issue and how can I fix this? I'm also experiencing super low fps. PLEASE HELP!!!