Yes, a picture is worth a million words. I just got an oncidium (one of the dancing lady type) and the bulbs and leaf edges do have some purple tinging which indicates it is getting the optimum and maximum amount of light it needs. but that looks very different from a rotting pseudobulbs. A picture would tell all.
looks like too much light....or at least more light than its used to....if you have only had it a few weeks then it probably came from a shaded greenhouse, and when you moved it up to more sun it made it go purple....i wouldnt worry about it....gl
Is the whole pbulb that color, or just one side? Just curious. Is the pbulb firm? I do have a Wilsonara that has one pbulb that on one side is brownish black, the other side is green - too much light too suddenly (the side of pbulb facing the light turned that color). That happened a few years ago, and it's not changed, so if that's what happened to yours, I think it will be fine.
If pbulb is very soft or mushy, then it's likely rot.