Hey Patrick (is that your sure name ?) or did i get it backwards ?
Id say you did very well regarding this is your first go at it. In fact i say you did splendid with the limited space and gear.
A few suggestion to fix some stuff.
Whitebalance
If you could get a hold of greycard that is actually grey, make a wb preset off that in the same light as you subject and you will get rid of the colorcast
Background
I know about cramped spaces lol, but i would try a darker bg fabric, and i would try to feather the bare flash over it, or simply center it to make a sepparation between the background and your subject.
Lightning position
As for the lightning i would try to use one flash to illuminate the background, and one to use a keylight camera left/right.
For fill use a foamcoresheet.
This will give you more depth in the image.
As i said before, the results are very nice given the gear and experience.
When i look back to my photos when i started out with just my sb800's i notice my lightning is kind of flat, i thought i needed to put light everywhere.
But the secret is to control to shadows where they fall and their intensity (yes in other words control the light spread)
Iv also learned that lightning position is crucial not only for product shots, but it makes a great deal for portraits aswell.
So i would suggest the same subjects.

darker background, move one of the speedlights to the background, and dont use the 100w spotlight.
Get a foamcore sheet for fill, to open up the shadows on the oppsite side of the key light.
Dont forget that you can go along way with just one speedlight and a foamcoresheet. Less is often more when it comes to light, especially of you dont have the means to control/modify it.
Hope some of it will be useful.
/Paul L.