Please investigate. Vomiting
may not a disease in itself, but a sign observed in many diseases. Vomiting (I'll call it as - Regurgitation) for 15 days shouldn't be taken lightly. To start with - you can get a chest and abdomen x ray
done - to identify if there is any radio-opaque foreign body, and send blood sample to identify if there is any metabolic involvement. Hope this is helpful.