OS X Text Replacements sometimes not working? This is a weird problem, I write a lot of different languages on my computer, and since my keyboard doesn't have all the keys in the world, I have made certain key-combinations that replaces them with another letter.

For example, "†˛" becomes "þ" and "∂∂" becomes "ð". Now that works fine, but I have also added "œœ" that is supposed to become "ǫ", but form some reason that special replacement does not work while the others do.  EDIT: To be able to type the ǫ letter I must also press space ("œœ "), while the others work perfectly to write in a word without pressing space. 

Is there any reason for this? I'm using the Yosemite 10.10.2, the same problem exists on the 10.0.3 DP.
From what I can test empirically here, the text replace function handles 'letters' differently from 'other characters'.

For instance, I can replace ## with € in the middle of a word, yet I cannot make qq do the same thing, it demands either a space, or for me to click on the confirmation box that springs up.

I'd perhaps suggest as a workaround, use a less letter-like trigger.
If it doesn't spring a confirmation box, then it will replace mid-word.
!! @@ ££ $$ etc all work just fine.