The spelling of the phrase "my own sweet self me" may seem confusing at first glance, but it is simply a matter of understanding the pronunciation. Using the International Phonetic Alphabet (IPA), we can break down the sounds of the phrase: /maɪ əʊn swiːt sɛlf mi/. Each sound corresponds to a letter or combination of letters in the traditional spelling. So, while it may look unconventional, the spelling of "my own sweet self me" accurately represents its pronunciation.
There is no recognized word or phrase in the English language as "my own sweet self me". Consequently, it cannot be found in dictionaries or hold a formal definition.