Bec, over on the old Child Neurology forum, was told by her allergist that it takes 6 weeks to get all the dairy out of your system. She had a lot of post-nasal drip. Five weeks into going dairy-free, it cleared up. It did not go away gradually, more of an overnight thing.

In Tom's case, two weeks into our dairy-free experiment, he had dairy withdrawal symptoms - seizures. (He has epilepsy, and it turns out that dairy was his biggest trigger.)

All this to say, it could still be the dairy. Give it 6 weeks, and then see if you react to it.