not feeling oneself

not feel (oneself)

To not feel physically or mentally well; to not feel as one normally should. I'm sorry for getting upset at you earlier. I just don't feel myself today. I know Mary hasn't felt herself ever since her cousin died.
See also: feel, not
Farlex Dictionary of Idioms.

not feeling oneself

 and not feel like oneself
Fig. to feel upset, troubled, or disturbed in some way. I'm sorry I said what I said. I'm not feeling myself today.
See also: feeling, not
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • not feel (oneself)
  • not feel yourself
  • not feel like (oneself)
  • feel (like) (oneself)
  • feel out of place
  • ace
  • ace (something)
  • an ace
  • feel bad about (something)
  • feel (some emotion) about (someone or something)