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Vertigo or dizziness
may be due to central(or systemic/brain) or peripheral(EAR) cause.
If there is any abnormality in the internal ear that leads to imbalance and dizziness.
Ear piercing usually done at the ear cartilage
or on the avascular plane so there is chance of infection to skin or cartilage , but will never cause dizziness and vomiting.
, high or low glucose may cause similar symptoms.
I would suggest you to see a Physician for check up.