What Causes Fatigue Along With Muscle Aches And Nausea?

I m debating about going into be seen by my primary... seems silly since my symptoms are flu like, except it s been going on now for 4 weeks. extreme lethargy. muscle aches (neck, shoulders) headache. nausea. no discharge from nose, but air is dry here. started almost 4 weeks ago and not getting any better. comes and goes.. daily; worse in the evening. Best after lots of sleep. I have been treated successfully for hypothyroid for years. seems silly to go in; plus I m exhausted! Flu epidemic here in Spokane, but I ve never had symptoms for a full 4 weeks! Is there really any value to going in to see PCP?