Introspection?

The following comes from Yam HaChochmah, teachings of Rabbi Yitzchok Meir Morgenstern in his explanation of Tanya.
It is damaging for a person to ponder too much about his personal situation. Even though it is proper to examine ones behavior daily to see what behaviors need to be rectified and in what areas he owes thanks to Hashem, still one must remember that God does not come to a person with unreasonable criticisms. It is wrong for a person to live with a constant fear that perhaps his behavior is improper in some way. This attitude flies in the face of knowing that God directs the world. God gave each person unique abilities and situations. Trying to overthink that perhaps you are fooling yourself shows a lack of belief.
Even though you must serve Hashem to the best of your ability, you must also rely on the fact that God is all-merciful and He will help you complete your task. To achieve this understanding truly takes much work.