pain sensation vs painful sensation

pain sensation and painful sensation both are nouns.

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

As nouns, pain sensation and painful sensation are synonyms defined as:

pain sensation and painful sensation: a somatic sensation of acute discomfort

Other synonyms of pain sensation include pain.

pain sensation (noun)	painful sensation (noun)
a somatic sensation of acute discomfort	a somatic sensation of acute discomfort