Traffic lights not working satisfactorily

I was cycling on the A106 and I wanted to cross over to marshall rd so I decided to wait as a pedestrian and cross the junction. Eventually my turn came and I crossed but when I got to the island two cars coming from the leyton direction were ignoring the signal so I looked at the pedestrian countdown with still 5 seconds to go I made my way across but a black bmw wasn't having it and he continued as if I wasn't crossing. I remonstrated loudly that the lights were in my favour and he said no they weren't. At this point I triggered into no I'm going to stand my ground and the incident escalated but eventually a passerby intervened. The traffic came to a standstill and this could have been very ugly. In the 39 years I've lived in London this was the worst. I'm 68 this year. Because of the way the incident happened I'm convinced the traffic light is not giving the right information to the drivers coming from the leyton direction.