I Don't Know What Is Wrong With Me

I feel bad because I told my cousin I'd come over and chill with her but then I got into one of my moods where I didn't feel like being bothered and I slightly don't feel good either so she got a attitude with me telling me she had other plans and could've stuck with them. I don't mean to be this way but a lot of times I just don't want to be bothered and socialize. Also a lot of times I say yes to things I don't even want to do just to prevent a argument and I do it a lot with her . Also when someone's really pisses me off I just want to totally dismiss them and I know it isn't right 😩 I don't Want to be a people pleaser and I don't wanna feel bad for saying no