I have felt the same way lately.I know it is because I have more responsibilities than I feel I can handle sometimes.Everyone thinks I am strong and show great confidence which most of the time I feel confident but inside I always feel I can be better.With that said i get angry when others do not care or seem to care how they act.An example would be driving...the way people run red lights,don't use turn signals,etc makes me ANGRY.
You are not alone but talking about it helps.I have a therapist.
Good luck!