My 2.5yo has become completely obsessed with loud noises, to the point he tells us he's worried. A few weeks ago we had builders in, who annoyingly started drilling below his bedroom when he was napping. He woke up completely terrified to the point I had to cradle him. Since then I've had to sit with him at bedtime. But now in the day things that never bothered him before like the bin men, he used to wave at them, he cowers behind me, even when they're quiet because he's anticipating noise. The hoover, the kettle, cars outside, even us walking upstairs while he's sleeping....its getting abit ridiculous. Should we worry this is more than the builder event, could it be early autism signs? We're at a loss what to do. He has quite noise in his room but he seems to jump at everything now day and night