Anxiety and Worry

Can our actions (or lack of actions) give us things to worry about?

As I have observed, those who plow evil
and those who sow trouble reap it.

~Job 4:8 (NIV) 

What should we focus on instead of worry?

⁵ Trust in the Lord with all your heart
and lean not on your own understanding;
⁶ in all your ways submit to him,
and he will make your paths straight

~Proverbs 3 (NIV)

Can worry alter our circumstances or change our lives for the better?

{Source}

 Is there anything to be gained from anxiety and worry? How does it affect our lives?

Anxiety weighs down the heart,
but a kind word cheers it up.
~Proverbs 12:25 (NIV)

Is anxiety and worry caused by "wrong" thoughts or sinful actions or are there other sources?
While anxiety and worry can be cause by sins, it can also be caused by not being able to let go of issues and problems in your life. Deal with the problems in your life and you will be at peace.

{Source}