The order of the colors in a color wheel is the same as that in the color spectrum. The order of the colors goes red, orange, yellow, green, blue, indigo, violet. This can be remembered by the acronym ROY G. BIV.
You can send the order back. Avon gives all reps one free return shipment a month. Also, try to get the money before you order the items. You don't get...
It sounds like you have over-toned. Stop dying your hair and it should fade back to a brighter hue. You could also try washing your hair with a clarifying shampoo...
Rip out a piece of the old mortar and bring it with you to the store. Then you can compare the color to the different options that they have available.