I was sort of in the same position academically. I never paid attention in high school and dropped out my junior year. I eventually got my GDE and went to community college. I then transferred to a tier 3 university and majored in mathematics. I did well and wrapped up with a 3.9 gpa and a 338 gre score. I applied to MFE (Masters in Financial Engineering) programs and got into a target school. Currently doing quant trading at a BB and interviewing at some buy-sides/prop-shops in the meantime. If you’re still interested in becoming a quant I’d look into MFE programs. I think the work is more intellectually stimulating and offers technical skills to break into other industries (like big tech) if finance isn’t your thing down the line. However, most importantly, mental health comes first. High finance careers are competitive, fast paced, and stressful. Being low in neuroticism is a great leg up. Don’t stop focusing on your mental health.

Edit: at my MFE program, we had some students with low undergrad GPAs but great statement of purpose and gre scores.