One of the most important parts of learning vocal technique is learning what feels right and what doesn't. Good teachers will often work on this with students by asking how the student thought something went ("Was that better or worse than last time? What was better about it?") before offering their own feedback. This isn't easy, but it's critical.

When I'm practicing, sometimes I'm just doing something wrong. If I can't fix it or I can't even figure out what it is, but I know it doesn't feel right, sometimes I just stop that practice session. That's when I know I'll be practicing improper technique. I'll try again next time and remember to ask my teacher about it in my next lesson.