As @ptrblck said, one of your error is that you should add nn.Flatten before nn.Linear.
Another, change first line
model = nn.Sequential(nn.Conv2d(32, 32, kernel_size=(3, 3), stride=1),
to
model = nn.Sequential(nn.Conv2d(3, 32, kernel_size=(3, 3), stride=1),
as your input is a tensor with 3 channels.