A shopper who helped a woman who had collapsed said it was terrible East Midlands Ambulance Service had no resources available to attend the incident.
It is believed the woman had suffered a head injury after collapsing.
She was spotted by a customer of Morrisons and her son as they left the Newark store.
The female shopper, who asked not to be named, went to help. She called 999 at around noon on Saturday.
She said she was initially told an ambulance would be sent but was called back 20 minutes later by EMAS and told none were available.
Her son ran to Newark Ambulance Station, on nearby Queens Road, but no one was there.
The woman said among others who stopped to help was a nurse who spoke to EMAS on the phone.
It was decided to take the victim to hospital in a private car.
“Not only were there no ambulances but there were no first responders or paramedics,” the shopper said.
“It was terrible. She was in a bad state. She was just starting to come around. She was very confused and disorientated and she was crying and touching her head.
“There should have been something available. I understand that ambulances get called out but there needs to be more paramedics in cars who can bridge the gap before an ambulance can get there. There aren’t enough resources in this area.
“There was nothing we could do as a group other than take her to hospital ourselves.”
'Those with a life-threatening injury or illness have to be seen first'
A spokesman for EMAS said the 999 call was assessed as not life-threatening and they had aimed to get an ambulance to the patient within 30 minutes.
She said paramedics and nurses in the control room had been in contact with a nurse who was with the patient.
She said they received a second 999 call to say the patient no longer needed an ambulance as they were being taken to hospital by someone else.
She said ambulance crews were not based at the Newark station and once they had collected their vehicle and checked their equipment they were out on the road responding to 999 calls.
Mr Greg Cox, paramedic and general manager at EMAS, said he was sorry they were not able to get to the patient sooner.
“Every 999 call is assessed based on the information we are given by the caller,” he said. “While we aim to get to all patients as quickly as possible those with a life-threatening injury or illness have to be seen first.
“On Saturday our crews were very busy and responded to 30 life-threatening emergencies in around Newark.
“By cancelling the ambulance we were able to free a crew to respond to the next emergency call.
“The patient has not contacted us to share her concern, however, we are keen to speak to her to talk through how we handled the call.”