It could most probably be tonsillitis and a throat
pain, difficulty swallowing, fever, scratchiness in the throat
, post nasal drip, malaise and loss of appetite are symptoms of tonsillitis. It can be caused by bacteria like streptococcus or it could be a viral infection. Bacterial infections need antibiotics. Taking the antibiotic for the required amount of days may help to clear the infection. Steam inhalations and salt water gargles can help.