does this happen to anyone's kefir?

So I strain the grains from the kefir. Kefir looks good
I taste it, seems good has alittle sour taste like its supposed to.

I put it in the fridge cause I hear by doing this & leaving there awhile, it elements all the lactose.
I check it after 10hrs or so, and in the fridge the kefir has
seperated into thick kefir & whey. The whey is on the bottom?
I drank a bit of the thick kefir part, tasted fine. Should I
be stirring the whole thing up & drinking it stirred?
Does this happen to anyone else?

thanks Tweet