Any one of these inputs could have been different, and the entire perspective regarding the decision is changed. Like the butterfly effect. Whatever you think you are in charge of in your own mnd is a result of those previously mentioned inputs and the subsequent chemical changes that occur in the brain in the form of neurotransmitter compounds such as dopamine, tyramine or endorphin.
There are hormones that are produced at the moment of orgasm, like oxytocin, that most definitely effect the direction of ones choices or decisions. An imbalance of the thyroid hormone thyroxine can cause one to be either terribly tired and drained, even depressed, or, overly optimistic, impulsive, and aggressive, all of which can and will directly or indirectly influence any decision believed to be made of "free will".
Free will is silly illusion. A decision is at the mercy of the neurotransmitters, whether a person feels hungry or full, desirous or satiated, happy or sad, whether they are using logic (pre-frontal cortex) or they are using emotion (amygdala). No one is in charge of their internal workings or their external environment, both of which influence any decision a person can make, thus the idea of free will...is just a silly illusion.