I am so sorry you caught the flu! If your shoulders are hurting that bad then take a wash cloth, wet it with cold water and stick it in the microwave for about a min. This will make it hot and it should help with the pain if you place it on the area or lay back on it. Try to stay bundled up and get as much rest as possible. I know how a bad immune system plus flus are. I had a bad immune system in middle school to the point I was out of school every other week and teachers had packs of homework ready for me so I could do my homework ahead of time while I was out sick. 
My day was good and pretty laid back. I should have been writing but.... LoL called to me so I kicked ass and took names ^-^