What is the difference between いかなきゃ(ikanakya) and いかなきゃいけない(ikanakya ikenai)? From what I read in a forum, ikanakya translates to 'I have to go'. The confusing thing is why does adding ikenai to ikanakya (ikanakya ikenai) mean exactly the same thing (I have to go) and not 'I do not have to go'?
Sources:
https://www.japan-guide.com/forum/quereadisplay.html?0+77952
https://www.jref.com/articles/imperative-forms.111/