Fine

This means one of 3 things;
1) I'm fine and I actually am fine/okay I just cba to use a better adjective

2) I had a BAD day and just need some price and quite
Or
3) I feel soooo mad I could punch you in the face but at the same time I do need you to talk to me about this now!

I'm fine really I'm fine.... okay I'm not fine..... I'm FINE talk to me please