Lexapro Side Effects

Hi! Has anyone experienced side effects of brain fog, and feeling really slowed down and a weird feeling with Lexapro? I am on day 10 of 5mg of Lexapro and I’m feeling incredibly slowed down, like delayed reactions and feeling like I’m in a dream like state. I was also diagnosed with mono almost 8 weeks ago as well so I’m not sure if it’s that or my medicine, or a combination of both. Any advice is welcome!