I said "you too" when the security gaurd at the airport said "enjoy your flight." It happens Op, but you wont see that person again so the awkward moment only last for a moment.
Once, I was at a restaurant and when the waiter brought my food, I accidentally said "you're welcome" instead of "thank you". He gave me a weird look and walked away.
"So the awkward moment last for a moment" true... But what if it is the same pizza man that delivers to his house o.o then it might be awkward in future occasions too. Uh-oh.
It's not a bad thing, as a matter of fact, I personally think that it is polite. That is why I say all the time over the phone (to end my conversations). *I love you*
who knows? maybe the pizza guy said the same thing, and when OP said "im sorry, that was an accident," he said "well i meant it.". as he winked her goodbye
After a tough day at work, ordering pizza and telling the delivery boy to enjoy his movie...! Weirder still, he told me to have a nice weekend (it was a tuesday)
The mother? She couldn't react because she wasn't there, OP got a text from his/her mom saying "I love you" and instead of OP texting her back with "I love you too" OP told the pizza guy that. The mom was not over the phone to be able to hear the whole ordeal go down, so she can't really have a reaction to this, unless OP told her afterwards. Which would make sense since OP decided to tell the whole world.