Has anyone else experienced these symptoms?

So I am currently seeing my doctors and have other appointments scheduled as well. About a week ago I started to feel extremely off balanced in my head and it started to affect my memory where I could not remember what I had just read whether it be a sentence or a few words. I had never felt like this before and it just happened randomly and every morning that I get up the first hour after getting up I feel fine and can recall and remember things just fine, but after an hour i feel some really drowsy, off balance feeling in my head and then the memory problems start. I had an MRI done two days ago and they said that it came back normal. They don't know what is causing this and they are still just taking lab tests to see what will show up. Has anyone else experienced these kind of symptoms where you feel fine when you wake up but after a couple of hours you start to feel light headed, off balanced and drowsy as though you're drugged up on something and have memory issues?

Has anyone else experienced these symptoms?
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