Hi gaarbon,
welcome to Questions & Answers..
I can understand you may feel annoyed, you could try contacting the retailer, but to be honest the price on products can vary from retailer to retailer. One may have a promotion running for a week or so and then reduce the product further the next week or return it to the pre reduced price.
I'm sure we have all been in this position at some time, I know I have, the problem, as I see it, is that you can either buy a product when you want it or wait and see if the price gets lower as the weeks and months past by, only problem with this is that a new model may come along and they the cycle starts again..