<s>[INST] My boyfriend has come down with sudden illness. Symptoms: Fever, getting worse Shivering - he says he feels freezing Muscle Ache Headache Lethargy Was fine all day, came on suddenly with a headache, now about 3 hours later, no better, seems to be worse? [/INST] Hello, A blood routine test is advised. Due to fever and infection, the body gets fatigued faster and leads to muscle aches and pains. Post blood test a medicine for infection should help reduce the symptoms. Even paracetamol will help reduce fever and pains. Hope I have answered your query. Let me know if I can assist you further. Regards, Jay Indravadan Patel, Physical Therapist or Physiotherapist </s>