Qty discounts issue over multiple product lists

So I have applied quantity based discounts to a category… worked awesomely for the nappies that my client sells. When i created a new discount for a different category it activates the nappy discounts as well… even if I apply the discount at an individual product level and not at category level it still activates all the other discounts. We are using the free version… is this limited to only one category??
I created product lists for various categories… eg 1) nappies 2) wipes. I have defined a separate product list inside the discount for each one. when i add nappies into my cart to apply the discount, it automatically applies discounts to wipes even tho they aren’t even in the cart and puts sale signs on every single product list that I defined even though they are all tied to different discounts. Help please… reluctant to buy the full version if this cant be sorted.