Makeup Help & Guest Post

I have a recipe guest post over at Pearls and Curls.
Check her cute blog out!
The other day I bought something.
A new makeup purchase, to be exact.

Does anyone else get nervous about buying new makeup?
My face seems to be really sensitive, but I love makeup.

I had a $2 coupon for L'oreal so I figured I'd try this-

It was pink and fun looking.
It's so light and airy.
I've never felt anything like this before!

It's soft and smooth, no streaks.

I just didn't know which shade to pick, as there were so many close ones.
...and...
Question: 
MAGICSMOOTH Souffle...now that I have you, are you a foundation? 
Under eye concealer?
Do I use you in combination with my Bare Minerals foundation, or all alone?
I fear this may have been an impulse buy, but do any of you use souffle on your face?!

Help! :)