Vitamins has a Kindle edition out now. It was posted here on BCTS, but readers asked for an ebook version (along with some other titles of mine) and it's available here:

Vitamins at Amazon US 
Vitamins at Amazon UK

As always, I warn that the basic story is still available here at BCTS (although Amazon might make me take it down) so if money is tight I understand you not purchasing the ebook. In any event, I always revise and expand on any of my posted stories before they become ebooks; sometimes a few hundred words and sometimes whole new chapters.

And as always, please post reviews at Amazon and Goodreads and anywhere else--and do it for all the BCTS authors on Amazon, please!
Karin