Disaster with the Munton's Oaked Ale

I left the Munton's Oaked Ale for a fair few days before taking a look. I expected it to basically be finished. I was in for a heck of a shock. It looked awful, as you can see from the picture. The bubbles were much brighter and browner than normal, almost yellowy, and still very active clearly, but worse, the discussing looking scum on the top. It was horrid, and surely a sign of infection. I will leave the beer to see what happens but I'm pretty sure it's had it.