Hello and hope you are doing well.
Kidney stones and ejaculation problems may not be related. Kidney stones are formed due to the deposition of minerals salts within the urinary tract. And frequent ejaculations could be hormone related. I would advise you to consult your primary care physician for evaluation. He may do blood counts, urinalysis, lipid profile, and measurements of creatinine, liver enzymes, and free testosterone in the blood.
Hope this helped and do keep us posted.