Feeling like the worst mom ever

I constantly lose my temper. Unless I get a break from my kids, I'm always on edge. I literally feel like shit because this is exactly how I didn't want to be. I never wanted to be like how my parents were with me but it's like no matter how hard I try I'm EXACTLY like them. My mother caused me to have major anxiety issues because of her overprotective and highly critical ways. I never want my kids to be damaged because of me like how I was damaged by my mom but it's like I'm stuck. What should I do?