Lex, you gotta get outside. Sit on the front/back steps or walk a few blocks down and back up again.
Staying in for too long will depress you. I know it's cold out today but it's also envigorating and the sun is shining. Bundle up and go for a quick walk. Force yourself to. You'll feel a bit better after you have-even if you don't think you feel bad. You'll definetly feel a little happier.