I am going to write this without trying to disrespect you, rather possibly try and guide you into some sort of enlightened way of thinking.
If the same thing is happening consistently, take a step back, look at the situation(s) that you have been overwhelmed with and meditate on it.
I say this to subtly emphasize something important, and that is, magick is in truth, no matter what way it’s spun, or what denomination you derive from, a path of self enlightenment.
Even some of the most powerfully enlightening evocations of the grandest demons and angels bring everything back to this - that being some type of personal or spiritual revelation.
With that all being said, I believe instead of revenge, you should look at why the situation happened, and the situations that occurred prior to your employment being terminated, and try banishing the negativity that caused it, and try warding against the same negative energies coming back into your life to prevent it happening again.
For this, personally, I would recommend using your preferred Divination method to ask your spirit guides and your ancestor spirits to explain why it is happening, and provide a vision of truth in how to prevent it again, and base a protection spells foreground on what you see and feel.
Use corresponding herbs to combat the specific type of negativity, if you use herbs.
If you use the spirits, ask the specific spirits that would be suited in combating this type of energy, invoke them and become one with them.
I hope this helps in some way.
Good luck (: