[Neonight]

The level you were in before it started warping you was most likely not finished loading, yet. In about 50% of the levels, if you walk out of one level and into another, there's a good chance you'll be warped around a bit before the level loads.

So, basically, I think the levels have not finished loading and they're trying to load, let you walk, AND go to another level all at the same time.