kidney stones

So related to my old previous post. I had a CT scan done and it was discovered I have a 2mm stone in both kidneys, that was 2 weeks ago or so. My urine culture was discovered to be negative a day later for UTI's. A week ago my back pain was minimal or non-existant and I guess my kidney stones are gone but this past Monday I went to a follow up appointment with a Urologist to check for a UTI and discuss why I get them so much or experience symptoms when theres no UTI. On Tuesday night I was napping on the couch on my side but went to sleep in my bed and slept on my side there too. Today around the afternoon I began getting back pain where my right kidney is. It doesnt go away completely sometimes and now I'm wondering if its the stone or if I dont have the stones anymore and the pain is possibly due to a UTI. The Urologist wants to check for the stones around January but do a 24hr collection of urine in the meanwhile to see what they can find.