There's many examples of her work causing alot of Discord in Ponyville, like making a doll irresistible to everypony and paraspites eating everything but food. Oh what fun she is! ... and no pony really holds any of that against her.
Oh yea, gotta add the sharing of 'should be forbidden knowledge' making a love potion to little fillies. Srsly, what if those three made more than a small potion of that stuff and somehow gotten it everywhere in Ponyville?
Okay, Twi, how do you want to handle this? Tell Discord it was a mistake and let him mock you for your lack of control and forethought or imply that it was all planned in some kind of weird kind of way but wasn't a prank? I don't think either will make your relationship with him any easier to handle!