Oh, oh,,, what did I touch?

I must have done something wrong.  I was trying to read a couple of threads, but everytime I click the button to open up the thread to read all of the responses,,,,, the responses change to an inverse order.   The very last response of the thread is at the top of the first page, and it displays the responses in reverse order all the way to the very first response of the thread, at the bottom of the last page.
A total PIA to deal with.  How can I correct this?
look to your right and it says SORT.....click that....
Ah,,, Thanks!   I don't remember initially doing that???
I’m glad to know I’m not the only one to do stuff like that! The office staff or my wife has to help my computer “skills” frequently.
My seven year old grandson keeps all my schitt straight on my phone and kindle and I can't thank him enough. Enjoy the music