Need a safe place to vent. I need help.

I became pregnant and I came off my psych meds. I’ve become such a short tempered mother to my three year old since then, and when I say the guilt is too much.. it’s too much. Not that it isn’t deserved. I mean, what kind of mother yells at a THREE YEAR OLD? I get mad at her for exhibiting behaviors that she’s witnessed from me, how the fuck is that fair? I’m so scared I’m ruining our relationship forever because for some reason I’m 26 and incapable of managing my own emotions. Lately I’ve been feeling like she would just be better off if I wasn’t even here. I wake up every day planning to be better, telling myself I’ll keep my cool and talk to her when she makes a mistake because we all make mistakes and she’s a baby. But then I clean the same mess over and over or find the meal she asked for hasn’t even been touched while shes crying for donuts or she yells at me (wonder where she got that from) and I just snap. I yell instead of talking. On the real bad days I even go to a different room and throw things but it’s not like she doesn’t know just because she isn’t seeing it. I’m a narcissistic mother and I hate myself for it. All I see on TikTok are teenagers telling their stories about how their narcissistic mothers have caused them so much pain.. I don’t want that to be my baby. I just don’t know what to do. I don’t know HOW to stop myself from yelling and being this horrible mom. I use to think just because I don’t whip her that I’m doing something so much better than my parents, but I’m not. I talk to her like an adult once I’ve calmed down, I apologize and explain myself, but come on.. apologizing without changing is pointless. I can’t afford $80 a week for therapy, I can’t take my medicine, I can’t smoke cannabis, I have nothing to help me regulate. She doesn’t deserve to suffer for that. What kind of mother even needs those things? What do I do? How do I calm myself?