I go back and forth between thinking I'm too mean or too

I go back and forth between thinking I'm too mean or too nice. I've decided. I'm way too nice. Like annoyingly nice. It would help to be a little meaner. It's silly. Being resilient, having standards for myself, others always made it into a bad characteristic. When I said no, I was being mean. When I finally snapped, you had the audacity to ask if my bad mood was because of my period. How conceited does someone have to be to not think for a second that maybe I was "in a bad mood" because of them? I still don't understand how being confident in things I'm good at, is me being up myself, or thinking I'm better than others. It all seems like deflecting. And maybe being mean is the best thing for me.