MIDI Output Note Duration

I recently went through about an hour and a half of work trying to hook up my keyboard to my computer to transpose a piece. After figuring it out, I used the keyboard and it wouldn't make the note the length I played it out to be, it was just what was selected in the notes. e.g. I had a quarter note selected, played a C on the keyboard for 2 seconds, and it came out to be a quarter note.

Is this an issue, or is it simply impossible to make music like this?