What Causes Fatigue, Weight Gain, Anxiety, Itchy Rashes, Fever And Concentration Difficulty?

Symptoms include fatigue, weight gain, anxiety, dry skin, itchy rashes,low grade fever of unknown origin, headaches, poor concentration, very low energy,low blood sugar, hair loss, facial pressure, sinusitus, mood swings. Had a very high positive test for Lyme disease was determined false positive one test with high c reactive protein ,next was normal. My thought is thyroid with pituitary dysfunction and or mild cushings. I ve had many tests ..some of which tsh 0.83 and urine free cortisol 96