Is this what you are trying to show:
That is whats appearing as your profile picture (the pic at the top of your user profile), however what you probably want is an avatar (the pic that shows up beside your post).
Its a common terminology mistake.
To change your avatar, go back to your UserCP and scroll down on the left side to the 3rd block labeled 'Settings & Options', select 'Edit Avatar' and do pretty much the same thing you were doing when you set your Profile Pic