Great stuff - especially for a first at anything, never mind a 3d programme.
I can't quite work out what's going on with the shadows etc., but this is likely a limitation on my part. (The small sphere at the back doesn't cast one the way the other two moving spheres do? Er... I think, but I'm really not sure so probably best to take no notice.)
Great colours and an interesting mix of shapes and materials. I like how even the spheres are very individual and the transparency of the materials varies a lot.
I might like a small change to show up the cone better. The white on grey doesn't seem to do it justice. (Maybe just a darker grey?) Also, I think the flatness of the background undermines the 3d effect a little.
But these are niggles at most. Overall, this is really well done. Can't wait to see more as you master the programme (or mistress it, if that's more appropriate).