I agree with the advice to talk to the preceptor first.
If nothing changes, nothing changes and all you can do is complain. You need to be your own advocate here. I disagree the person who said to ignore the person and go to the manager. This is usually not effective. Even if the preceptor takes it badly, doesn't change a bit, it's worth it to get your feelilngs out in the open rather than feel like a punching bag.
Ask for what you need. There is nothing wrong with saying "Since inserting an NG is something I haven't done, I would have appreciated it more if you would have talked me through the steps while I was doing it, rather than wait to the end and point out my mistakes because that wound up being uncomfortable for the patient and I felt completely inadequate. I shouldn't have to feel that way because I was unfamiliar with the procedure.".
Because if you feel like a punching bag and dcn't say or do anything about it, you might as well stand with a sign that say "punch me" because you're allowing it. Obviously those that do the punching need to stop but I hope you get my point.
I tell the new grads I precept to please provide me with feedback, because this experience is about them learning. While I would be bothered if someone didn't like my style, I would appreciate a face-to-face talk prior to the preceptee running to the manager. Because I think we would have a more amicable departure, or even perhaps I could work on my skills as a preceptor. I wish I got $4000 bonus. That's generous. However, in light of that kind of money, you have a right to good "customer service" from them.
If nothing else you can make it easier on the new grad.
You're feelings of inadequacy and not knowing anything are normal new grad feelings. Most of what we learn is on the job, because there's no way to learn everything in every kind of job in nursing while you're in school.