Hello Welcome in H.C.M. As you had told in your complaints that you are having sore throat, fever with chills, nausea and loss of appetite. you are already having high blood pressure and congestive heart failure though under control by medicines. Your symptoms are in favor of Acute upper airway infection and that may be associated with conditions having fever with chills like Malaria, U.T.I., or pneumonitis because patients with congestive heart failure are more vulnerable for pneumonia. Thus now it becomes necessary to do these investigations- 1- X-Ray chest. 2- Culture & sensitivity of throat swab. 3- Blood- CBC, MP, Widal test, SGPT, 4- Urine - Routine and microscopic. Though most likely you are suffering from viral pharyngitis but above basic investigations are necessary for other possibilities if any one is there. you may take now- a- Tab Paracetamol. b- Warm saline gargling. c- Antacid with PPI. d- Take proper rest. I hope this will help you. Regards.