Are these stills from a cell phone or camera/camcorder? JPGs? What are their pixel dimensions?
How are you importing these photos into Premiere Elements 11? What project preset are you or the program setting for this project?
What computer operating system is your Premiere Elements 11 running on? And, whether Windows Explorer or other, what is the orientation of the still at its hard drive save location?
Depending on the circumstances, you may end up having to rotate the still on the Expert workspace Timeline by selecting it, rotating it via Applied Effects/Applied Effects Palette/Motion Panel expanded, and scrolling down in the Motion area to use the Rotate feature there.
We will be watching for your follow up.