What's a file extention lmao

[Nightmares]

I literally don't understand what's wrong I JUST WANT A GIF FOR MY AVATAR AHHHHHHGGGG

I'm trying to get this ^ as my avatar but it says it's an incorrect file extention or something?
I spent the last 15 minutes editing it so it was under 260-something kb -______-

Thanks ;__;

 

[Peter]

It's saved as a .jpg rather than a .gif

try this:

 

[Nightmares]

It's saved as a .jpg rather than a .gif

try this:

Ahh, I'm so sorry for the trouble, thank you!