For temporary relief from sinus pressure and headache, you can take Ibuprofen or Acetaminophen. For your throat pain, warm salt-water gargles and throat lozenges work well. For a severe cough, an over-the-counter cough syrup containing dextromethorphan (for dry cough) or guaifenesin (for wet cough) can help. Oral decongestants like pseudoephedrine can ease sinus congestion, but avoid nasal decongestant sprays for more than 3 days. Stay well-hydrated and rest. Since your symptoms are severe, please consult a doctor to get a proper diagnosis and ensure you do not need antibiotics.