Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concerns..
As per your query the symptoms of fever,
sore throat, fatigue along with nausea and chills and coughing up of mucous can be due to
Influenza or flu while can also be due to lung or
chest infection..
As it is already 4 days, you should consult an ENT expert or a Pulmonologist and get evaluated and he can advise you to get throat swab culture done along with blood tests and chest x ray for confirmation of cause..
You can be advised a course of antibiotics like Augmentin or
Cephalexin along with a combination of Ibuprofen and
Acetaminophen..
You can also be advised to take mucolytics like Ambroxol, anti allergics like Levocetrizine and also do warm saline gargles, steam inhalation..
Avoid spicy and chilled foods..
Sip on plenty of warm water and do warm compresses over the chest..
Hope this information helps..
Thanks and regards..
Dr.Honey Nandwani Arora.