There are restrictions like this all over London to prevent large vehicles like HGVs from using the street, but also make shedloads of money from PCNs against small vehicles that are nervous of using the narrow lane on the left. Clearly you have never seen one before. A Toyota Aygo would easily pass the narrow lane I would have thought.
So any particular reason for not obeying the direction arrows ?
The video shows a London black cab passing through the narrow lane in the opposite direction just before your car approaches, so clearly there was enough room for your little car.
This may not be game over, because cases like yours can sometimes win on what is known as a "collateral challenge". This could be camera approval or a fatal error in the PCN or their not following the legal process, so wait a bit to see what others say.
