Clear runny nose, little pressure in head headache with warmth to it. is it allergies or should i take amoxicillion?

Allergies: Clear nasal discharge is probably not infected, but you may have congestion which would cause pressure to build up in the sinuses. For that you need a decongestant like pseudo ephedrine. But you also need antihistamine to prevent the runny nose and congestion in the first place. If you need antibiotics, you should take it with a doctor's guidance. A steroid nasal spray is a very good treatment

Runny nose: Allergies or cold, i would not take an antibiotic. You should see your doctor and determine what is the problem. A cold should clear on its own.