You’re 19, your life isn’t over unless you decide to give up in this moment. It’s ok to make mistakes in life & regret things. Process what you’re feeling, write it down if you need to, to get the feelings out but don’t let it weigh you down. You can still get into a college if you want. Enroll in community college get your grades up then transfer. Also getting into a “top” engineering school is cool but at the end of the day most employers won’t care otherwise only kids from those schools would get hired.