Beating yourself up
I once interviewed a head who had taken over a failing urban secondary school. Two terms in, he told me he was ready to give up. Behaviour was still a problem, attainment was stuck, exhaustion was setting in - maybe someone else should try?
He said as much to the chief education officer who, instead of agreeing, listed the head's achievements: structural changes; sound, values-driven strategies that were starting to take effect. All this was visible to a knowledgeable observer but in the head's troubled mind his success was drowned out by the background noise of constant short-term crises.
In the end he picked himself up, going on to national recognition and eventually retirement.
What is the right thing to do?
You might not have a boss who highlights your achievements for you - so do it yourself. Write them on a sheet of paper. Make a deliberate effort to move out of the "I can't do this" mindset.