Yes, you know it already, you should always try to think positive no matter what happens or what challenge gets in your way. But sometimes – it IS ok to have a bad day! As long as you do not allow yourself to stay in that mood too long. But it is normal that some days just are not that fantastic, or, you feel that they are not as fantastic 🙂 Allow yourself to get angry, to feel frustrated or sad, it is well needed at times. But as you know, after rain comes… sunshine. And your personal responsibility is to not let it be more than just A bad day, never several. Get out of the negative feeling or frustration as fast as you can, and try to change your focus. Maybe you talk to a friend or loved one that you know will make you feel good, or you go for a run to clear your mind, or, yes, do a longer yoga session with meditation. Mindful meditation and/ or running is usually what gets me on the right track again, sometimes also with the help of talking to a person I have trust in, that can help get perspective on things. Find what suits you best.
I wish you the best. Take Care. Namaste.