Occasionally, in any field, you get a bad professor. I would suggest taking classes from another professor if there are any available. If you still do less well than you'd rather, perhaps you should consider changing your major then.
Honestly, I like the piece. I agree with what a few people have pointed out and agree they maybe didn't like all the negative space in the corner.
While critique is always useful, comments about how you don't belong in your major are less than professional. I would listen to the comments that you can actually can apply to your work and avoid taking classes from people like that if at all possible. I think you'll find most professors will be willing to help you if they aren't pleased with your work.
I also think that in any arty sort of field, criticism can be more emotionally difficult because the things we make are so much a part of ourselves. I do think it gets easier over time, however, and you can learn to look at your work in a more detached fashion.
I say give it a bit longer. The problem is, with anything you study you might encounter a professor who does not do his or her job correctly and changing your field of study might not mean you avoid that problem. On the other hand, if you took textiles classes from people who were helpful and gave you sound advice and useful criticism, I think you might find it very rewarding in the end.
Your piece is creative and interesting. You seem comfortable with different stitches and things and it seems competently done. The colours and textures are yummy. I'm pretty sure you don't suck at it.
You might just have to change things a wee bit here and there to please your professor, sometimes.