Oh, ok. I was going by the D diminished, but that works better. Fixed.
Curious, is this similar to the reason we use C/Eb/F# in C Minor key instead of the diminished (C/Eb/Gb)? These chord variants always seem to trip me up, even when I think I use the correct chords/get them right.
Try and think less about note combinations and more about the underlying theory. For example having a tonic diminished chord in a minor key (or even a major key) given the context, just doesn't make sense. But if you look past the repeated chords and look at it a bit more horizontally and in the context of voice leading, then you'll see that it's just a chromatic neighbour note. Look for elements of theory and let that guide you, not individual notes.
Also in the middle of the 2nd or 3rd line on page 2 (I forgot where, I'm on my phone) where the bass note changes from E flat to E natural on the bar line, a courtesy accidental would help.