Brain fog after upping from 30 to 40 mg

Hi everyone! I started prozac early July and have slowly upped from 10 all the way to 30 mg which helped out for a few weeks, but I recently started feeling depressive symptoms and my doctor upped me from 30 to 40 a couple days ago. I’ve been having really bad brain fog and just feeling of it/cognitively impaired and high. Will this go away?