No need to be scared that you acted as a “nice guy.”
It is not that girls do not like nice guys.
They just don’t like guys who are indecisive, grovel and always agree with them regardless of whether they have a varying or opposite opinion about something.
There is nothing unattractive about being concerned for your crush’s well-being and asking her about how she is feeling.
What you do need to do though is ask your crush out.
Now, that is decisive. That is what girls like.
A guy who goes after what he wants.
If you just remain on the sidelines and make small talk with her from time to time, you will soon see her giggling as she exchanges flirty messages with her new boyfriend on her smartphone.
Instead of worrying about whether you were a nice guy in asking her about how she feels and whether she is feeling better, your focus should be on asking her out the next time that you see her.
Regardless of whether she agrees to go out with you or not, you would still be a winner for being decisive and going for what you wanted.
That winning attitude is something that girls absolutely love.