What Causes Tiredness, Headache And Shivering With History Of Malaria?

Hi there, I had malaria and blackwater fever almost 3 years ago to the day. Over the last few days I have been feeling really tired, sore, headaches etc. I ve heard that it can reoccur on an annual basis? last year, I had the shakes etc, but this time around I feel similar to when I first contracted malaria. I guess the question is, is it life threatening or if I do have symtoms will they pass on their own. Thanks Rees