I would have never asked for the upgrade, even to pay. This is likely this could not be processed in flight anyway and it takes the focus away from the problem: you feeling nauseous.
I would have accepted the call for a doctor, whom would have the authority to ensure you were lying down in a safe space. A call for a doctor does not necessarily mean a diversion.
You were right to not take the pill IMHO, I agree you must know what this is.