Wow. A lay man telling off a specialist presumably O&G specialist to be ignorant. But you are right that most period cramps are not caused by disease and its perfectly normal to experience it and hence it couldn't be solve if there is no problem at the first place. Someone can control the symptoms however with medication or other methods.

If you visit a doctor you genuinely looking or expecting something pathological might be happening and therefore either seeking problems to be soughted or ruled out and to be assured nothing sinister is happening. The specialist did ultrasound to rule out causes of pathological bleeding such as endometriosis, uterine fibriod and chocolate cysts. You don't go to doctor knowing there is nothing wrong with your health.

The irony here is that the ignorance doesn't lie with the specialist who did years of trainings and exams to qualify as a professional but the person asking for some unrealistic cure.