Dear Michael, hello.
What was the status of your girlfriend immediately after the injury. Did she recovered completely in these 15 days or the symptoms you have mentioned were there from the day one of the injury.
in the arms could be due to cervical spine
injury which should be taken care of immediately.
My advice will be- get MRI
done of her head and neck and thoracic area and consult a Neurophysician as soon as possible.