Emma Wilson was one of the first people in the queue and arrived at the store 11 hours before it was due to open.
People seemed to be "appearing from nowhere"
The 18-year-old said she was joined by a few people and was well looked after by Ikea staff who provided blankets, coffee and packed lunches.
But as midnight approached she said the volume of people went up "alarmingly".
And despite the earlier concern for customers, she said she was "disgusted" with the store in the way it handled the crowds when the doors opened.
Ms Wilson said she first became concerned when "the security guard...admitted he was scared of what might happen."
Ms Wilson, from Ongar, Essex, told BBC News: "I am recovering from a car accident where I injured my leg and as the evening wore on I began to worry about how controlled the entry to the store was going to be."
She said she was assured by the operations manager, store manager and head of security that "no one would have to run".
But added: "By 11pm the police and security team were trying in vain to prevent people from entering and leaving the queue.
"This was causing more agitation in the crowd as was the number of people who seemed to be appearing from nowhere and gathering just metres from the barrier right by the entrance."
Ms Wilson, who went to the new store with her father and boyfriend to buy a sofa, said the ceremonial "cutting of the log" was carried out, barriers were opened and the crowd "charged towards the entrance".
"I was in great distress as both my dad and boyfriend who had been queuing with me were taken out of sight and I was crushed against the concrete pillar and into the rows of shopping trolleys.
"Needless to say I didn't even set foot in the store instead stood screaming because I was so scared until some other members of the public who also wanted to get out of the crush helped me over the trolleys and into the car park area.
"I could see hundreds of people being crushed and the security (guards) at the entrance were overwhelmed as crowds pushed past them into the store.
"I also saw other people who had been queuing just behind me turn away because of the violence with nothing to show for sitting waiting for 12 hours.
"I am truly disgusted with Ikea's approach to security and lack of concern for personal safety for the public and their staff. The organisation was completely pitiful."
As a minor consolation Ms Wilson did manage to leave the car park with a voucher guaranteeing her a sofa.