Personally, I don't think that Bitcoin is a bubble and I definitely don't think that Ethereum is a bubble since the crypto market is always like that and 70% retracement is very common in this space. I think the price goes down because of its rapid grown, we went from 10usd to 1000usd so the market needs a big correction to stay healthy. Also, Ethereum is a platform for hosting ICO and it required people to buy ETH to invest in which is why the price has risen so fast.