Hello and welcome to HCM
The highlights of your problem are headache and feeling of pressure at back of the head. Besides your nose is clogged with yellow colored mucus.
You need to get culture and senstivity of the yellow mucus. Culture will identify the micro-organism causing the infection and sentivity will identify the most appropriate antibiotic to which the micro-organism will respond.
The headache may be associated with the infection affecting the nose.
Is there is associated fever
. If yes, you can take an anti-pyretic.
Feeling of weakness may be associated with the same problem.
Consult your doctor for clinical examination, investigations and management.
Thanks and take care.
Dr Shailja P Wahal