Kidney pain 27 weeks.

Rachel
Hello all, 
I have been having some what I think is kidney pain on the left side of my back for about two weeks.  I go to the dr Tuesday but wondering if anyone else has had this and knows what it is.   I drink plenty of water 30-75 ounces a day.  I've been drinking some cranberry juice too hoping to clear out an infection. 
Thoughts?