How should I handle this?

How should I handle this? I'm in med school and at times we're assessed through presentations ...where we have to individually present to the whole class. A month prior to this, I explained to the examiners about my condition and they all said I have to "overcome" On the day of the presentation....I couldn't say a single word how ever much I tried ...after then they said it'll be okay ......fast forward the test results came back and I was the only one who failed ...I asked them to reconsider all in vain. Now I have to redo the 6 week course unit again 😔