Hopeless

I've been having the worst anxiety of my life. It started on Saturday March, 16th and it just hit me randomly, there was nothing specific that triggered it it just came out of nowhere and I just started feeling super anxious. I'm 18, turning 19 in May and most of it stems from really terrible mistakes I've made in the past when I was 16-17, the thought of everybody hating me, being alone in the future, and imagining myself not accomplishing anything that I want to. I just started feeling scared, guilty, worried, nauseas, depressed, and unmotivated. I keep trying to tell myself that I'm a better person now and that I've changed but everytime I start feeling calm it's like my mind keeps telling me to feel bad about my mistakes and I start beating myself up again and thinking that I'll never get past this. I have friends and family that have been here for me and have told me that I can talk to them whenever but I still feel alone. The other day my anxiety got really bad and I tried hurting myself with not much success which is something I never thought I'd try doing. I've never gotten professional help cause I've always been scared of worrying my parents but the other day I told my mom about my anxiety and depression for the first time and she told my dad to make an appointment at some place my younger brother goes to. I'm not sure if this'll help but even though my mind keeps discouraging me about things getting better I still have a bit of hope.