Fever for 7days. What is happening?

Had a bout of stomach upset and slight temperature 7days ago. For that took O2 and paracetamol 500 for 3days. Stomach became ok. But fever upto 103°F with chill, periodically hit me after 8 hours. Noted the pattern slowly. My family Doc, upon inspection found my spleen and liver enlarged and suspected Malaria. Gave blood sample for Falciparum and Vivex Antigen and got the course for Malaria started immediately (he had twice successfully detected MP before reports came in). But the reports turned negative this time and the fever hasn't left yet. Three days ago,he gave whole lot of Blood tests: TC DC ESR, HB, Platlet count, Widal, SGPT, Bilirubin, MP along with Urine for C&S and Chest X ray PA which was duly done. All reports are within normal range or negative. ESR is 18mm, SGPT 67U/L and Unconjugated Bilirubin 0.22mg/dl (T. Bilirubin 0.91) are slightly on the higher side. My Doc says, its not alarming. Awaiting Urine C&S.100°F Fever came today. What is happening? Frustrating!