I now own one bitcoin in my coinbase wallet. It feels good. I am not sure why it feels so good but it does. I have a good feeling about Bitcoin. I am already up 20 euro after today. What could possibly go wrong.

It's Coinbase that owns your 1 BTC.
This. How many times it needs to be said that unless you control your private keys, you are not owning said BTC? You need to get that BTC out of Coinbase immediately and download Bitcoin Core, Armory, or at least Electrum, or get a trezor, or a paper wallet... any of those options are a million times better than Coinbase.