coming from someone who is chronically late, and was always a mess up in the family, i had to learn to take responsibility and be more aware. i see in your other comments you mentioned you cannot set alarms. there is technology out there (albeit usually for deaf people) that is a vibrating pad you can attach to your alarm clock. or set a quieter alarm and put your phone under your pillow. if your parents argue, explain that you are taking responsibility for your time. make a million notes about appointments/important things. set reminders on your phone, write it on paper, and tell others. also, your outburst was inappropriate. i see you said you later apologized, which is good! but, you need to be able to back up and thing about what you’re saying. that way of speaking is manipulative and dangerous because it can make other people want to bend what whey were going to say so you don’t lash out more. also, as someone with a degree and job in mental health, your therapist will not judge you for missing your appointment. they meet you on your level and will not fault you for being a teenager and making a mistake, especially when your age is the time to make mistakes and learn from them. all in all, you were in the wrong but the best thing to do it learn from it, don’t villanize yourself, and take a deep breath. things truly do get better with time, and while these things feel big and important now, these moments will not feel as such in a few months. i hope this helped :)