The opening of an inquest into her death heard Tamzin, who was a student, got out of the car and crossed the road before climbing the crash barrier.
She was hit by a vehicle driven by a member of the public and sustained fatal head, neck and chest injuries.
In a statement released after the hearing, Tamzin’s mother Amy Hall described her eldest daughter as her “best friend” and said the death had left their family “devastated”.
“Tamzin was the most kindest, caring, loving, loyal girl ever,” she said.
“She was my shadow from the moment she opened her eyes in the morning until she went to sleep at night.”
Ms Hall said Tamzin, who was diagnosed with autism spectrum disorder, was “my absolute world”.
“She was such an intelligent young girl and had such interesting perceptions on things in life,” she said.
“Tamzin was my absolute everything and I can’t believe she isn’t here any more.”
The IOPC investigation will look into what contact the police had with Tamzin prior to her death, including their actions, decision-making and risk assessments of the situation and whether these followed relevant training and policies.