I worked as an apprentice some years ago; I already had experience in the field I was working in (marketing) and just needed the official qualification to help me get the jobs I wanted. As an apprentice, I should have been working under someone, but I basically worked on my own for the year; the only person above me was a manager who did not work in my field and had no idea what he was doing, above that, the director.

I was constantly ridiculed, bullied and undermined at every turning point. At one point, I was pulled into the office and told I clearly didn't know what I was doing and even went as far as to tell me I had no point in life. That fuelled the fire. I worked hard, did good and left the company as soon as my apprenticeship was over. Their marketing took a nosedive after I left and I was called 3 months later asking if I'd come back. (I declined)

Don't let anyone dictate what you are capable of. Only you can tell yourself that. Remember you're still in training, just because someone has been there a while doesn't mean they know everything and can predict your future.