What Could Tiredness And Muscle Pain With A History Of Hyperthyroidism Suggest?

Hi I am 45 have a history of hyperthyroidism which has been under control for 5 years. I have recently been feeling tired, unrested, with muscle aches and pains. Just been tested for malaria (as I live in Kenya) and came back negative - symptoms put down to viral infection. However I keep getting tingling in my hands, and toes, numbness in my lips and today dark brown spots have suddenly appeared on my left hand - don't know if that is relevant however! Can you help?