Hello from JustAnswer. I am sorry that no Neurologist has responded to your question.
To address each of your questions.
It is impossible to determine from the symptoms alone what is making this happen. The Neurologist is correct that it could be a sensory seizure or a condition that presses on the nerve to this location, but it would require further evaluation to determine whether these are present. MS also is a possibility, as MS can cause virtually any neurologic symptom, although this would not be one of the more common cause of such symptoms.
It is not a concern that this could be related to tweezing the nose. Yes, it is possible that inserting any non-sterile foreign body into the nose can create a risk for infection, and infections of the upper airways can rarely penetrate into the brain. But someone with an infection around the brain would have far more severe symptoms than what you describe, including profound sickness, fever, significant headache, and altered mental status.
No, this is usually not something that warrants an ER visit and it would be fine to make an appointment. Certainly, if someone starts with a sensory seizure and it then generalizes, that would warrant urgent attention, but the symptoms that you describe are not indicative of a generalized seizure. If you have some of these symptoms and then lose consciousness, that would be worrisome and it would be appropriate to be seen emergently.
If I can provide any clarification, please let me know.