Why are some ppl so cruel?

I’ll start off by saying I’m 18 years old and have been trying to save up for my own phone and car. I have a phone that I paid for myself but my mom got mad at me one day and reported it as I stole it so now it’s locked and I can’t get service on it. In order to get service I would have to buy an unlocked phone. So i stupidly ordered a phone on Facebook marketplace for $300 and they blocked me right after I cashapped them. I work my ass off for my money. I was lucky enough to get a hospital job for the state but I still only make $10.47 an hour. Im just so ashamed with myself bc I’m trying to save up for my own car and phone and I would like to move out of my narcissistic mother’s home and eventually go to school for nursing (I already did my first 2 years). I guess I just wanted to vent. Please no negative words, I know what I did wasn’t smart but I’ve learned from my mistakes. I’m going through a hard time and this was just the icing on the shitty cake. I just feel like I’m a good kid but nth ever good happens for me.