Hi,
Absolutely fine of getting negative thoughts. Its all about how you going to react or respond to such thoughts.
Though I could understand your situations, scaring about reality doesnt help you. You have to face it with confidence.
You are just 23yrs young and have got lot many things to explore and achieve in life. Better late than never. Start working on yourself first to bring changes in your life.
Next Steps
Ask for help either to your friends or family or professionals. Thats the first step to bring changes in your life.
Health Tips
Write down on a note book how you wanted to live your life rather than suffering from mental ailments. Set your prioritize and ask for help.
Best wishes!