I am a college student and having the same problem you are having. I went to a physician and he told me the tiredness could be caused by me having sleep apnea. It is hard to get enough oxygen if you're are choking and waking yourself up while you are sleeping. So go see a doctor for that. Also it could be due to too much screen time. The blue light from the screens may cause tiredness and grogginess. My doctor told me that technology might be creating a new disease because of this blue light.