I have had a sore neck, dizziness and poor appetite/sickness feeling for past 4 days. i recently took a long hall flight. could this be a cause?

Sick: certainly you could have gotten a viral infection while traveling. make sure you are drinking adequate fluids. If no better in another day or two, I would see your primary care physician or go to an urgent care facility. I don't think at this time you need to go to the emergency department, unless the symptoms get worse or you develop other symptoms.