Looking for some peace of mind

I just sold my ethereum after a little over a year of holding and made out with a pretty considerable profit. I intentionally timed it so I'd be in the long-term capital gains bracket. I moved my ethereum over to Coinbase to sell and accidentally "sold" it into USDC rather than USD. I immediately changed it to USD within the minute. I'm aware that every crypto swap is considered a "taxable event" and from my understanding you're just paying taxes on the gain between transactions. I should theoretically just be paying the long term gains on the first transaction of the ETH swap and almost nothing if anything on that split second where I switched between USDC and USD. I want to confirm this is the case and I didn't just somehow blunder the long-term as opposed to short-term capital gains tax.