I would keep the windows covered at night to lessen the effect of artificial light on your sleep. Surely some natural daylight brightens your room a bit with sunrise? If not, I would recommend you get either a dawn simulator or just a timer you can plug a light into that will turn it on at a specified time (much less expensive). I have had a dawn simulator - the kind you plug a light into that gradually turns up the intensity over a 45 minute period. I absolutely love it, couldn't do without it in the winter when it is very very dark here in the mornings. I know they cost a hundred bucks, but they last forever. Mine is called the "Sun Rizer", basically a programmable rheostat. I wouldn't get one of the ones that has a lamp/light as part of it, just get one you can plug any lamp into.