Green’s Dictionary of Slang

1. drunk.

1927		The Charleston Chasers [song title] Feelin’ No Pain.
1953		L. Uris Battle Cry (1964) 333: Two cups later and Andy felt no pain.
1970		J. Bouton Ball Four 82: Johnny Podres, the old Dodger [...] was there [i.e. the pub] , feeling little pain.
1975		J. Gould Maine Lingo 28: A gentleman feeling no pain might be bungs up on his way home.
1983		J. Byrell (con. 1959) Up the Cross 121: By the time Big Oscar and Lady Cynthia got back [...] they weren’t feeling much pain.
1998		R.G. Barrett Mud Crab Boogie (2013) [ebook] Two glasses of vodka and Ruby’s Red grapefruit juice were sitting on the coffee table next to the bong and neither of them appeared to be feeling any pain.
2001		J. Stahl Plainclothes Naked (2002) 297: I am certain that Mister Bush [...] would not have agreed if he hadn’t been, as the saying goes, feeling very little pain.
2008		J. Lansdale Leather Maiden 122: ‘He had a flask [...] Time it got late, he was feeling no pain’.

2. unconcerned, casual; a state achieved with or without drugs.

1953		J. Thompson Alcoholics (1993) 36: I’m feeling no pain, for the moment.
1965		G. Melly Owning Up (1974) 196: She [...] tried hard, although obviously feling no pain at all, to make herself weep.
1977		C. McFadden Serial 35: A euphoric bunch smoking dope [...] (they were passing time with a friend who had a broken arm but was feeling no pain).
2002		R.G. Barrett Mystery Bay Blues 246: It wasn’t bad pot [...] Les was laid back on the couch feeling no pain.