Must have been the nerves. I agree that back when she started she really was a handful, but over the years she has grown into her own and has become quite good live. I'm talking Dua levels of evolution.
I mean, look at the fear in her eyes in this one while wishing everything is over quickly (keep in mind this is from 2009)
I love Ellie but I saw her at a festival once, around 2010, and she was even worse than this