On Tuesday, Nancy creates 12 clay pots * 2 = <<12*2=24>>24 clay plots.
So she created a combined total of 12 + 24 = <<12+24=36>>36 clay pots on Monday and Tuesday.
Subtracting this from the number of clay pots she ended the week with means she must have created 50 – 36 = <<50-36=14>>14 clay pots on Wednesday.
#### 14