Hi and welcome to HCM Thanks for posting your query here. The symptoms seems to be with pharyngitis. Pharyngitis can be caused by bacteria like streptococcus, staphylococcus and some viruses also. Any how you have been treated with antibiotics for 5 days, then most of the infection will get controlled. Some times the bacteria may affect the sinuses also which will result in sinusitis. It presents as headache and heavyness in head. Along with the antibiotics if you take some antihistaminics and paracetamol 650mg it will be helpful to relieve the headache. Steam inhalation will also work. Antibiotics are drugs which will act against the bacteria. They will show affect on bad as well as good bacteria. This good bacteria will be present in our alimentary tract which will produce some sort of vitamins to the body- called as symbiosis. Hence while using antibiotics these will also get reduced. Hence it is necessary to take some multivitamins to overcome this. You are advised to take multivitamins and drink lots of fluids. Hope this is helpful to you. Regards