Did they tell you were it was? It all depends on where it was lost. If lost in AMS it will usually be on the next flight, if lost in the USA I wouldn't be surprised that it will take a few days to reach you.

With KLM my experience is that my bag didn't make the AMS connection (XXX-AMS-LHR) and came along on one of the next flights. Now I guess that AMS-LHR is slightly more frequent than AMS-TRD....