I'm sorry your course tutors are giving your confidence a knock - try to remain strong, not everyone will like your work, it's a very personal thing, some will love it, some will hate it (sorry not to sound harsh lol). If you find joy in what you do, if you work hard and like what you create, that's probably an important thing. There's no point in creating what 'they' want if it's not right for you. And anyway, you said you're passing, so seems you ARE doing it right. If you weren't doing things right you would fail. And even then you can work on it and improve.

If this is what you like and what you want to do, stick at it. Even famous artists (I know it's graphic design but just an example) were told they weren't good by some people.

I don't rate a lot of art that is 'famous' and popular. Picasso for example, I think he was.. sorry to say it... rubbish. I saw some of his pieces in barcelona, and if I were his teacher (lol) I would have failed him!!! But they would sell for possibly millions.

So... do the task as you're told, but don't be too upset if people don't see what you're trying to do or appreciate it. Other people will. And you're doing enough to pass so they must like your work. You probably take the 'critisism' very personally when it is really guidance and they see a way you can improve. I can't handle critisism at all so I'm not insulting you, just saying perhaps when people say it's not right they just see a way it can improve, and that's why you're studying this in the first place I suppose. Hang on in there x