A good friend gave me this answer today: "In general, 'confidence' can be understood to be "confidence in something" which could also be confidence in one's own abilities or attributes -- but 'self confidence' ('aatma-vishwaasam' in Malayalam, 'than-nambikkai' in Tamil and 'atma-vishwaas' in North Indian languages) means specifically "confidence in oneself," directly related to 'self-assurance' and 'self-belief,' in terms of being a source of inner strength and conviction, especially giving oneself the confidence to overcome obstacles and achieve goals." I found two direct references to this sense of the term in the book "India: a Million Mutinies Now" by Nobel laureate Sir V.S. Naipaul, and these references also give the Indian equivalent term for self-confidence as "atma-vishwaas." This, taken together with the other 2 answers given by kind members here, does seem to make a useful distinction between the two expressions.

A good friend gave me this answer today: "In general, 'confidence' can be understood to be "confidence in something" which could also be confidence in one's own abilities or attributes -- but 'self confidence' (literally translated with the same meaning in the standard expressions 'aatma-vishwaasam' in Malayalam, 'than-nambikkai' in Tamil and 'atma-vishwaas' in North Indian languages) means specifically "confidence in oneself," directly related to 'self-assurance' and 'self-belief,' in terms of being a source of inner strength and conviction, especially giving oneself the confidence to overcome obstacles and achieve goals." I found two direct references to this sense of the term in the book "India: a Million Mutinies Now" by Nobel laureate Sir V.S. Naipaul, and these references also give the Indian equivalent term for self-confidence as "atma-vishwaas." This, taken together with the other 2 answers given by kind members here, does seem to make a useful distinction between the two expressions. I would, of course, welcome more answers and interpretations from all!