I would first ask what you are trying to accomplish by using promoted listings (PL)? You have sold 43 items in the last 90 days and currently have 38 active listings. If you are trying to increase sales there is no proof that the use of PL actually increases sales since there is no way to tell whether an item sold using PL would have sold as a generic listing.
I have never used PL and never will. Unless you increase your prices to cover the cost of the PL there are only two things you can be sure of with using PL. First you are increasing eBay's revenue and second you are reducing your income/profit. You are selling a lot of lower cost items that I suspect have a narrow margin of return once you deduct all your selling expenses. Using PL and adding to those expenses without having to adjust your selling price may further decrease your revenue or even push it into the negative.
