I don't even know how to respond to you. Saying "Little defensive there, huh" constitutes "mak[ing] fun of"? I'm not sure who's actually the sensitive one here.
Besides, pointing out ableism isn't an accusation. In fact, I don't accuse you of anything personally, I bemoan the joke. In the face of this, you retreat to a scenario where you are besieged every day by recreational Ritalin users in order defend your ego from maybe admitting your joke wasn't actually funny (or accurate).