1. its not a short version. its a different expression. personally, i don’t just text “kk”. i say that expression out loud too. its just a “cuter” way of saying “okay”, not faster.
2. “kkk” means you don’t really have patience for the person you’re corresponding with anymore. you’re like brushing them off…”kkkkk”
3. ya it takes much quicker to write ya than yes.
4. “he he” means you kinda just chuckled inside. you’re not guffawing with laughter like “HAHAHAHAHA” but you emitted a humor-ful sound from your throat.
5. “:)” does mean what you guessed it did. but it usually ends the conversation in a pleasant, not awkward way. not like ending off with one person saying a random line and then BAM- no more txting. it’s like..okay this is over 🙂
hope you gained some clarity. im quite the expert on txting lingo so feel free to ask more questions:)