"It is over now. Are you OK?"
Translation:Se on nyt ohi. Oletko kunnossa?
There's no particular reason for it; it just doesn't work that way. You can't combine olla and hyvin when you're worried about someone's wellbeing. You have to use kunnossa (the essive form of kunto, "condition/fitness").
- Oletko kunnossa? Are you OK?
- Onko kaikki kunnossa? Is everything OK?
If you wanted to ask more generally how someone doing (rather than worrying about someone's condition like in the sentences above), it's possible to use hyvin with the verb voida. That verb would be the Finnish equivalent of the Swedish att må in this context, except that it is far more formal in Finnish than in Swedish.
- Kuinka voit? How are you?
- Oikein hyvin, kiitos. Quite well, thank you.
A less formal way to do the same and use hyvin is to use the verb mennä.
- Miten menee? How's it going?
- Ihan hyvin, kiitos. Pretty well, thanks.