My kid has yellowish pee like this, orange stain in his diaper (urate crystals, I guess), and he cries for no apparent reason but when I checked, he's crying while he pees. He has no fever as of now and as jolly and lively as ever. Do you think it's UTI?

How old is your baby? According to this NIH article (https://www.nichd.nih.gov/health/topics/infantcare/conditioninfo/Pages/basics.aspx), newborn babies have various issues during the first few weeks after birth, including urination. And they can be easily addressed by the baby's pediatrician. NIH adds that when a child shows signs of distress during urination, like crying or pain, you should seek medical help right away. Additionall,, a light to dark yellow colored urine is just normal in a healthy child. But when in doubt, consult your child's doctor at once.