Time zones...Since when?

Well, you know how after Nashville Tennessee the time goes back an hour, right?
Apparently jumping across that line can be a little confusing.

(I went from Kingsport to Johnson City to Morristown to Louisville to Nashville to Indianapolis back to Nashville.)

I was leaving Tennessee on my own for the first time and my best friend and brother stayed on the phone with me pretty much the whole time I was on the bus. I called him from Nashville (after my phone recharged of course-I was stuck there for two hours) which is where the time goes back an hour so where it was 2 where I was it was 3 where he was.

Now keep in mind I had been up since 6 am so almost 24 hours.
The fisrt thing he says to me (not even a hello or anything) is 'Do you not realize what time it is?'
I was like 'Yeah its 2 I just stoped in Nashville."
He just laughed at me and said 'Hun youre an hour behind me now it's 3 up here.'after he was done laughing at me he asked 'Did you forget about the different time zones again?'(yes this happened once or twice before)
I just staired at my phone and asked 'Time zones...Since when?'
He just laughed again and said 'Yeah,hun,there have been time zones since the begining of time.You should lay off the coffee and get some sleep.'