That's so odd that kefir caused ur energy to drop. Most people report that kefir gave them energy.
Perhaps the kefir reaction was die-off? Or, I've also read that people with yeast issues have trouble tolerating kefir, for it can aggravate the issue.
The body is complicated!
By adding more fat, how has doing so changed your body composition? (better? worse? more muscle or "softness?" etc)