Database model for blood tests project

I’m developing a medical app (learning purpose) where users can store and manage blood test results, medications, doctor appointments, and medical documents. I’ve designed a PostgreSQL database schema, but I’d love some feedback on best practices, potential pitfalls, and optimizations. Functional Requirements: - User Authentication: Users can log in using email/password or Google OAuth. - User Profile: Stores name, height, weight, and other personal details. - Medical Documents: Users can upload, view, and organize PDFs/images of blood tests, prescriptions, and other medical reports into folders. - Blood Tests Storage: Users input their blood test values (e.g., TSH, T3, T4, cholesterol, etc.), and the system shows trends & graphs over time. - Medication Tracking: Users can schedule medications with: - Start date - Dosage (e.g., 2 pills per day) - Reminder times (e.g., 08:00 AM, 06:00 PM) - Appointments: Users schedule doctor visits and get notifications. - Notifications System: Sends reminders for medications & doctor visits. Users can snooze reminders (e.g., “remind me in 1 hour”). I want to be able to take inputs on how many doses the user needs to take, how often, at wich time, when did he start. Also if the user can not take the medication at the time of the reminder I want the system to make a new reminder an hour later.