Hello Friend, Good that you are seeking a help here. Overthinking or chattering mind, fear, insecurity etc symptoms of anxiety in your mind . Obviously with such preoccupied mind, you will notice only negativity and lack of interest in everything. Just observe and analyze, what's happening around your life in terms of job, career related pressures, relationships issues, financial issues, lifestyle etc. Any of these could be triggering such anxious thoughts. Be positive. You can overcome this with a help counseling support. Openly discuss your problem, ventilate your emotions. I am sure you will be able to find a solution to come out.

Hi It can be managed and overcome Consult with me or any psychologist for therapy and counseling All the best

Go for evaluation of your depressive tendencies. After knowing the level of depression it would be eafsier to start the treatment .

You need to break the vicious cycle of negative thinking. A psychologist can help you by suggesting some tips and change in lifestyle. 

Visit a psychologist to handle this.