Your modules are missing the return statement also you are not reassigning the activations in the second part of this forward method:
        x = self.conv1(x)
        x = self.batch1(x)
        x=self.PRelu1(x)
        x= self.max(x)
        self.dw_conv2(x)
        self.batch2(x)
        self.PRelu2(x)
        self.conv3(x)
        self.batch3(x)