I seriously feel that blender has a mind of its own. I tried doing the same thing today on Blender at home and it was doing random crap. First after i put the UV sphere along with the cube, i could not select the cube(it just did not allow me). I could only work with the sphere. I closed it and started with the cube and then the UV sphere, it allowed me to select only the cube, not the sphere. I got frustrated and closed it down after trying for 5 times. It is seriously crazy.