Cannot change folder names on my mac

[Duch]

I was renaming folders on my external Hard drive, and it kept asking me if I wanted to change the name, or keep it. I accidentally pressed to keep the old name on one folder. Since that has happened, I cannot change any name on any folder, whether it is on my macbook, or the external hard drive. Also when in finder, the up and down arrows do not scroll up or down (but work fine in safari)