pain sensation vs somesthesia

pain sensation and somesthesia both are nouns.

Word	Noun	Adjective	Verb	Adverb
pain sensation	Yes	No	No	No
somesthesia	Yes	No	No	No

As nouns, somesthesia is a hypernym of pain sensation; that is, somesthesia is a word with a broader meaning than pain sensation:

Other hypernyms of pain sensation include somaesthesia, somatesthesia, somatic sensation.

pain sensation (noun)	somesthesia (noun)
a somatic sensation of acute discomfort	the faculty of bodily perception; sensory systems associated with the body; includes skin senses and proprioception and the internal organs
	the perception of tactual or proprioceptive or gut sensations