At night I have difficult swallowing saliva and lately I have been very tired and get plenty of rest but wake up still tired and have no motivation to do anything.

And you haven't gone to see a doctor yet why exactly?

We know NOTHING about you - age, gender, weight, past history, diet, general health - the list goes on. You can't go online expecting answers out of context of an exam in person.

As we age, many of us have more difficulty swallowing because of weaker and atrophied muscles. When younger, swollen lymph glands around the neck can cause both problems you mention. But that's just ONE reason, and swollen glands are a symptom, not a disease in itself. Can you see why you need to be seen in person?