Mindfulness can sound far more complicated than it actually is. I like to describe it as being aware of what is happening as it is happening. It isn't the normal way of operating in our busy lives, so it takes a conscious decision and practice to become mindful rather than living in the past or future.
While I'm telling you to be honest with yourself, I'm not advising you to go into work tomorrow and leave a dead fish on your boss' desk with a note that reads "I quit, jerk!" It's not always easy to find another job, so your first plan of action should be to try and mend your current job "situation."