Negative energy tends to build in oneself, whether it's from darker times in your life, toxic people, or negative thoughts. Not only is it important to repent to yourself, but a good cleansing will help to melt away any unwanted energies. Take a day off and meditate for awhile; maybe visualize black tar dripping off of your body, letting a golden light shine through. Afterwards, I'd light some in sense, ground myself, and call upon a deitiy to help out.
This is just a suggestion, and you can chose to customize and substitute anything for things you are more comfortable with. I hope this helps!