What Causes Blurred Vision,tiredness And Body Pain?

I have days of being very foggy headed, my vision isn't sharp and I'm tired all day.I have muscle aches and pains that are not related to anything my physician finds. I've had lab test drawn. Sometimes I wonder if it's certain foods. I am not in a high stress environment right now. In fact there are days I can't seem to find the energy to run a small errand. Other days I feel great. When I discuss this with my physician it all sounds vague and it's written off as hormonal or menopausal. On bad days I am very non productive