You must take antibiotics and the earlier the better.
You are mostly having lower respiratory tract
at present you can take antihistaminic and decongestant tablet and paracetamol
tablet this will give you good relief.
You can also take steam inhalations this will give a soothing feeling.
But tomorrow do consult a doctor get done x ray
chest pa view and then antibiotic can be started .If there is lot of phlegm then you can get done culture and sensitivity of the phlegm so that organism is known and to which antibiotic it is sensitive can be known.