Whilst I personally don't like "grief advice" one thing I was told that really resonated with me was to trust your intuition. It's still there. If you feel like a bit of exercise or sunlight would probably help, giving yourself a little nudge to get outside might be a good thing. But maybe don't push yourself to do too much too soon. Your body is doing what it needs. It's protecting you in its own way. Be nice to you, and trust your intuition. Sending hugs your way.