It started to ferment
No. You are fine, it is doing exactly what you want it to do.
I don't understand. The starter looks fine. What's the question?
Flocculation. The yeasties are feeling done and wanting to settle down. Keep em spinning for your full starter time - they can sleep in the fridge
I have never seen yeast clump like that.
I just had a starter with EC-1118 and it did the same thing. It was pretty fun to watch compared to my (relatively few mind you) other starters I've done. Like a living lava lamp.