did i miss the point?

as part of an optional assignment this summer, i was told to create a worry list, detailing every possible trouble, stress, or negative thought to cross my mind.

once forming the entire list, step two was to mentally and logically go through the list, sorting through the reasonable worries from the foolish and useless ones.

step three was to then forget about the unreasonable worries and focus on how to change, improve, and eliminate the plausible list.

step four? enjoy life, worry free. or that was the eventual goal. 

unfortunately, i utterly and bitterly failed this assignment. i made it all the way through step one when i decided to quit. by the time my list of worries had reached #45, i had stumbled into a despairing and unhelpful gloom, surprised and downtrodden by my extensive list.

however, i didn't quit right away. as i attempted step two, my state of negativity made every worry appear reasonable, which further decreased my mood. 

since that fateful list, my mind has remained somewhat heavy and overcast. usually a positive person to the point of being unrealistic, i have been rather pessimistic consistently. 

but at what point are human emotions and moods controllable or incontrollable? is it my own mind allowing myself to remain in this leaden mood, or did my worry list really have such a lasting effect?

i have always believed that our feelings and emotions are pretty much uncontrollable-determined rather by situations, words, and our morals rather than chosen individually. 

but then you have to factor in our own responsibility and accountability. 

what distinguishes the difference between simply a bad mood and a serious issue?