28year Old Male. Fit And Healthy. Symptoms - About 6

28year old male. Fit and healthy. Symptoms - about 6 weeks ago got a fever and became dehydrated. Went into hospital overnight for hydration. In the last week extremely tired, few sweats, dreams (which is unusual), drinking up to 2 litres of water a day but still thirsty. Urine is very cloudy. Sore lower back.