Actually i think i understand what happened. I think it puts my sprites becouse of the sonic.horse files. i am not a programmer so i'm not sure if this is how it works. I tought the horse extension was a file that contained the sprites, but it actually loads them in real time.
This is why you can't save sprites outside of the costume horse folder. When i first opened the folder yesterday i only saw the .horse file. So when i loaded it, it called my sprite, wich i also named sonic, and since i tought the horse extension contained the files, i tought this was a repost. Sorry for the mixup, it trully was me and my pc. Sorry for writing the reply again, i should have phrased it better