Interesting questions being asked here. Daniela. indeed we hope to reach the place where kindness and generosity are our natural states of mind and that we are both kind and generous without being prompted. But equally it is easy to get carried away with ourselves and find that both kindness and generosity get smothered. we can even find ourselves feeling selfish and ungenerous. It is at times like this that it is helpful to make conscious reflections about the importance of these things and to prompt ourself in this regard. In particular I am suggesting that we investigate the idea of doing things for others as an antidote to those periods when we become self absorbed and perhaps even depressed. Being gladdened from doing kind things is a heart response and is not the same as being pleased with ourselves for doing so, which of course may haves traces of vanity in it.
with regards to your little knocks that come as a reminder that you have let slip your mindfulness, this is interesting. Some might even be inclined to believe that there is someone or something watching over them that just nudges us in the right direction from time to time. It doesn’t actually matter what we believe the source to be, if you can just allow it to function as a little nudge towards being more conscious. I don’t think you need to come to the point of expecting punishments every time you do something you might regret. There is a case to make for the idea that if we expect negative things to happen we increase the likelihood of them happening.