Thank you for asking. Your complaints are suggestive of anxiety problem. Not able to concentrate, over thinking, sleep disturbance, headache, bodyache, low mood, etc are some symptoms suggestive of anxiety disorder. For proper diagnosis and management, a detailed knowledge of these complaints is needed.
Next Steps
You must consult with a psychiatrist. You can ask a detailed query here on practo or visit one nearby you.
Health Tips
Do not worry. It is a common problem. With timely consultation and treatment it can be cured.