Nicola added: “He [Zac] was just keeping me so calm. He was saying ‘it’s OK mum, don’t panic, you’re fine.'”
Police and paramedics arrived shortly afterwards and Nicola was checked over at the scene and later told she had very low blood pressure.
Neither Nicola nor Zac was injured in the incident and, while the car was damaged, it was not written off.
They waited with paramedics for family to collect them and stopped for a drink nearby, with Zac treated to a free drink from staff after they heard about his bravery.
Nicola said it was “really unusual” for her to faint and she would be having further tests before driving again.
Nicola said the police officers were amazed at how calm Zac was after listening to the 999 call.
She said they had invited Zac to their Worcester headquarters to present him with a certificate for his bravery.
She described her son as her “little hero”, saying his calm reaction and quick thinking prevented their ill-fated Christmas day out from ending in a more serious crash.