Brief Answer:
One can only control one's actions

Detailed Answer:
Hello and welcome,

One can only control one's actions. If negative thoughts are coming in, don't take action on them. Take action on thoughts in which welfare of people around.

Overthinking and negative thoughts can be managed by the following:
- Continue to do your routine work
- Focus on something productive
- Have a healthy lifestyle, exercise more
- heave a healthy diet that is easily digestible
- incline towards daily yoga practices. Breathing technique and meditation can help reduce thoughts. There are many schools that teach meditation like Budha, Art of Living, etc. You can join one of the programs that teach meditation

Hope this helps.

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