how to resize a note horizontally

Using Ctrl + Alt + arrow doesn't resize the note but put all files on the monitor left or right.

It sounds to me as if something running on your computer has intercepted the key press before it reaches Stickies.  Maybe some software which helps manage your display driver, from your description?

Try checking through the options of other apps which are running in your notification area to see if there's anything in there about using those shortcuts?

Tom