Clear thick phlegm in throat. No cough or flu symptoms. Just stuffy nose and tired. Upper abdominal is sore.

Flu or GERD. Even without flu symptoms i would first think of a generalized or abdominal flu or gerd. Gastroesophageal reflux disease. Best see your primary care md or ENT specialist.
Consider. Trying a nasal steroid like Flonase at night. It may be all allergies. If used at night the steroid makes your post nasal drip into an antiinflammatory. A nettie pot will help as well. Get this better and see how everything else goes. Good luck.

Related Questions