I think that shortening/modification interjections in the language is a nessecity. Expressing rage, confirmation and quick commands are too long and too formal for what they intend to express. As well as this, common interjections in language are missing from the language. These are my suggestions:
Graddakh
Too long and unimpactful for a brief "f*ck!" moment; It's similar to saying "Gee willikers" or "Sacre bleu" in english/french. I think that "Grra" is far more satisfying, and condenses the explitive down to a nice, single-syllable statement. I've used it before when talking to friends, as well as a few posts ago in the forum.
Ai
Not overly complicated like graddakh, but it still feels weird coming out of the mouth. I suggest just making it the diphthong "Ay", making it similar to the "Aye" of oler english dialects or the japanese "Hai". It could also double as an "okay" word of general confirmation.
Affa
Too harsh for trying to calm a horse. You want to avoid fricatives as much as possible since a big stress inducer for a horse is running into a snake, and making snake sounds is the last thing you want to do if you want to get your horse to stop moving. I suggest making it a nasal or an approximant: "amma" or "awwa". Nice and calm.
For calming a baby you could use "affa", but
Mumbled response
The equivalent of "uh-huh" and "nuh-uh" in many, many languages. Asi mra lekh Dothraki laz vekha ven "oho" ha sekaan, ma "o" ha vosaan. The IPA would be similar to [˦˨ʔm.˨ʔm] and [˥˩ʔo] (it isn't exact due to this being a non-pulmonic sound)
