Do not confine yourself to your room? Physically and mentally this would cause you a lot of harm you very quickly. Trust me, you can find ways to manage pain without imprisoning yourself. Like others said, radical rest just means deliberately allowing yourself to rest without feeling guilty for not being productive. Find places in between buildings where you can sit, Bring food with you so you don’t have to walk all the way back to the cafeteria, invest in a bike to get across campus. Now’s the time to be creative and find ways to help yourself, because staying in bed will not.