Thank your for asking. I our complaints are suggestive of anxiety problem with disturbed sleep. Poor concentration, sleep issues, overthinking, etc are some important symptoms of anxiety problem. Major stress of worry about future, etc often is the cause. Unhealthy lifestyle, irregular sleep patterns, general stress, are other contributing factors. With suitable interventions and learning to relax one's mind and body, can help you overcome this problem. If required there is a role of medications for short term.
Next Steps
I would strongly suggest you to consult with a psychiatrist. A detailed evaluation of the problem is needed.
Health Tips
It is completely curable.