To what extent is the saying "If the world feels too small for you, do not say, 'Oh Lord, I have a great worry'; rather, say, 'Oh worry, I have a great Lord'" legitimate from an Islamic perspective?

The intended meaning of the statement is correct, but the phrase "So do not say: O Lord..." is incorrect. Rather, the correct approach is to command supplication, as in the Almighty's saying: "Call upon your Lord humbly and privately; indeed, He does not like aggressors." The prophets used to supplicate their Lord during hardships, as did Ayyub, Zakariya, Musa, and Harun, peace be upon them.