Thanks for providing more information.
As you describe,in my opinion you shouldn't ignore your symptoms as they get worse gradually over the time.
Possible causes may include Sinusitis,Cervicogenic headache,Cervical spondylosis,Tension headache.
You should take OTC Motrin instead of Tylenol as Motrin has anti-inflammatory effects and more effective than Tylenol.
You can take 200 mg Motrin every 4-6 hourly.
Also do gentle massage with muscle relaxant ointment and apply warm compresses with a heating pad on back of neck,shoulder.
Take short breaks of rest while doing work.
Take OTC Claritin.
You can take Sudafed
decongestant for 3 days.
Drink warm liquids.
Steam inhalation can be effective in your case.
And take proper sleep.
Use a humidifier in your room.
If your symptoms'll persist then consult your regular doctor for further evaluation and management.
I hope this helps.
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