Over thinking on your aspect defines a sense of pre-occupation/rumination about present existence and future prospects.
The fraction of thought also includes repetitive negative thoughts against which our mind tries to find alternatives that lead to exhaustion and reduced motivation.
The prime importance is to know the deep rooted causes of this and taking an initiative that leads to positive mental health.
Next Steps
Consult a Psychiatrist to start with appropriate treatment and to start with counselling sessions where you can ventilate your emotions.
Health Tips
Getting assessment of these symptoms for their severity (Hamilton depression rating scale).