Do you know what this worm-like creature is? - Video

Sent in to EG:

"I would like to ask the public if anyone knows what the worm lookalike thing is as our son was was playing in the sand at camp over the weekend (just North of Buller River) and it gave him a bite - like a mozzie bite, small red lump about 3-4mm diameter but with a puncture wound on the middle like a small hole, he screamed and instant tears. I put ice and an antiseptic cream on it and it came good within a hour.
BUT, when I put this in a container, and put a stick near it, it would stand up like a snake would do defending itself, Hubby and I were like "why is it doing that" was weird. We thought worm too straight away, but we were curious to why it would defend itself like it did, and the pain and wound our Son got from it?"

- Alanna