They were telling me to drink 3 liters a day or something and making me track my urine output with a pee bottle. I think I was doing something like 2500 milliliters not quite the 3000 they wanted but they were happy with that. I think any liquid is ok as long as it’s not going to throw off your lab work. The transplant dietician could confirm. I think kiwi and pomegranate juice are off limits forever but basics like tea, coffee, water and soda should be fine. For a while my blood sugar was up because of high prednisone so you might be a tad careful with high sugar drinks. But they were telling me to drink Diet Coke soda to get the phosphate up - I don’t do diet so I was drinking normal coke. It took me three or four weeks to get my creatine below 2. Which meant my new kidney was functioning good. It’s settled at 1.4-1.5 which is at higher end of normal.
That creatinine sounds like a good intermediate level. I don’t have many suggestions on how to drink more other than to pick liquids including food like watermelon or soups that you will enjoy drinking or eating. Salty foods might make you drink more but be careful as you don’t want to be dehydrated and still not drink. Regarding the pain I hope they have checked obvious things like a UTI? I think one of our recent transplant recipients was in the hospital extra post transplant for an infection like a UTI. Otherwise try to visualize/compare the pain of peeing versus dialysis. If the kidney kicks into life strongly then future years of dialysis related pain and stress go away.