D# major is Eb as pumpthrust notes - it does exist as a theoretical key but we tend to not worry about any of the theoretical keys such as Fb, G#, D#, A#, E# and B#
In Eb major you might get a D major as secondary dominant of G minor (i.e. a borrowed chord)
If it were D# minor then we expect to see F# in some chords
list out the progression as you believe it to be (including the spelling - what notes - are in each chord) and we will review it and identify
1) actual key (may involve respelling with the enharmonic equivalents)
2) chord function within that key
3) explanation of any borrowed chords
note enharmonic tones are as follows
Abb | = | G,F## | | Bbb | = | A,G## | | Cbb | = | Bb,A# | | Dbb | = | C,B# |
Ab | = | G# | | Bb | = | A#,Cbb | | Cb | = | B,A## | | Db | = | C#,B## |
A | = | G##,Bbb | | B | = | A##,Cb | | C | = | B#,Dbb | | D | = | C##,Ebb |
A# | = | Bb,Cbb | | B# | = | C,Dbb | | C# | = | B##,Db | | D# | = | Eb,Fbb |
A## | = | B,Cb | | B## | = | C#,Db | | C## | = | D,Ebb | | D## | = | E,Fb |
Ebb | = | D,C## | | Fbb | = | Eb,D# | | Gbb | = | F,E# | | | | |
Eb | = | D#,Fbb | | Fb | = | E,D## | | Gb | = | F#,E## | | | | |
E | = | E##,Fb | | F | = | E#,Gbb | | G | = | F##,Abb | | | | |
E# | = | F,Gbb | | F# | = | E##,Gb | | G# | = | Ab | | | | |
E## | = | F#,Gb | | F## | = | G,Abb | | G## | = | A,Bbb | | | | |
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