I am experiencing runny nose (worsened by: recent exposure to allergens) , cough (worsened by: lying flat) (quality: no phlegm or mucus) and sore...

Allergic? Viral? etc: Nose and throat symptoms can be from cold viruses, strep throat, allergies, etc... It can be hard to tell what the cause is. If symptoms only last 1-2 days, it is more likely allergies or irritation. If nose and eyes are itching, maybe it is allergies. If there is more coughing, maybe viral. Doctors have 5-minute tests for strep, so a primary care doctor can diagnose strep and start antibiotics.

Allergies: Allergies can cause all of these symptoms.