I'm worried I really fucked up.
Have electrum, have used it a couple times before. Wanted to buy some BTC from coinbase to toss into electrum. $450 worth.
Go to receive tab and copy the address there, put it into coinbase, send. Hours later, transaction is confirmed but no coins. wtf? Now realizing there is a "save" button there on the address tab, so I press it. Any advice?
Did coinbase gave you the TXID? if so, Can you post it here so we can know if the transaction is really confirmed.
Alco check if your electrum wallet is synced. There should be a green dot on the bottom right of it or blue if you're connected to a proxy.