discomfort vs uncomfortableness

discomfort and uncomfortableness both are nouns.

Word	Noun	Adjective	Verb	Adverb
discomfort	Yes	No	No	No
uncomfortableness	Yes	No	No	No

As nouns, discomfort and uncomfortableness are synonyms defined as:

discomfort and uncomfortableness: the state of being tense and feeling pain

discomfort (noun)	uncomfortableness (noun)
an uncomfortable feeling of mental painfulness or distress	embarrassment deriving from the feeling that others are critically aware of you
the state of being tense and feeling pain	the state of being tense and feeling pain