Headaches, tension headaches, muscle tensions, irritability, sudden intense burts of anger, difficulty focusing, etc. are all
signs of opposing energies.
I studied physics many years ago. There was another time where I was forced to be in proximity with a Jew. We were both aware of each other. His nose started bleeding. I was wondering about this for many years afterwards, but I think this may actually be another sign of opposing energies. There are many signs of opposing energies apart from the ones I listed above. If someone has a cold, has been blowing their nose a lot, is in a dry climate, is naturally prone to nosebleeds, etc., it would manifest easier.
In the case of xians, muslims and other non-Jews, the person with the strongest energy will overpower the weaker one, and the weaker one will feel the effects. An exception is if you are outnumbered.
It's a bit different with joos, since they are parasitic. If you you open up to them in any way by relating, as in building friendly rapport, you may feel the effects of the opposing energies even though you are stronger. This is why Satan states in the Al-Jilwah not to have friendly association with other 'people'. This is also the reason they will incessantly try to suck up to you, to get you to lower your conscious, or subconscious, spiritual defenses. If you are forced to interact with Jews at your job, etc., the trick is to stay professional and not engage in any meaningless conversation. Don't relate with them, and DON'T accept any gifts, food, snacks, etc. They will try anything to suck up to you.
Someone stated that the only thing muslims respect is overwhelming physical force. This is true. With Jews, you could probably beat them up, but they will go home and curse you. The only thing that will get THEM to stop is overwhelming spiritual force, black magick.
I'm not saying your friend is necessarily a Jew. Do you get any other side effects from interacting with her, apart from having nosebleeds? Try closing your chakras and shrinking your aura next time you interact with her.