How do I convince the doctor I have appendicitis?

So the doctor at my school IS convinced I have appendicitis, but the ER doctor isn’t. He thinks it is a ruptured ovarian cyst (this was yesterday by the way). I still have pain and I’m starting to heat up. I wont have time to take my temperature till later but I’ve had a couple mum’s feel my forehead and they said im burning up. The pain is in my lower right quadrent and is killing me (even the pain killers arent helping). The doctor said to go back if the pain increases within 12 hours. If it stays the same than to wait 36 hours and see if I still have it. It is a little worse, but not much. I’m just worried because I’m getting a fever.

I have all the symptoms of appendicitis but my blood work was fine and they didnt even see my appendix on the ultrasound so they figured it wasnt swollen.

I’m just really worried it IS appendicitis and not a cyst because I’ve had a ruptured cyst and this is a bit different pain, plus I’m sick to my stomach and now heating up. I’m afraid that if it is and they dont take it out it will explode.

How do I convince the doctor to remove it? I just want to make sure that it isnt appendicitis and if I get this pain again then I will absolutely KNOW it isnt appendicitis and wont be as worried.