I literally just kegged my attempt at BM's OktoberFast ale and I noticed that it was only active for maybe 24-36 hours and then basically did nothing for another 2 weeks. When I finally took a gravity reading before kegging, it finished about 4 points low. So, it seems from your description that you may be in the same boat.
Also, providing additional information such as type of yeast (strain, liquid or dry, starter, etc.) and whether you are going a true lager or an ale styled version(I assumed ale style since you referenced a swamp cooler) will help in trying to provide a more complete answer. Regardless, it seems like you will be just fine.