That’s also what I suspect but I don’t know how to fix it. Here is the model if you want to see:
class ConvNet(nn.Module):

    def __init__(self):
        super(ConvNet, self).__init__()
        self.conv1 = nn.Conv2d(3, 32, 7)
        self.max_pool = nn.MaxPool2d(3)
        self.conv2 = nn.Conv2d(32, 64, 3)
        self.avg_pool = nn.AvgPool2d(2)
        self.fc1 = nn.Linear(64 * 64 * 32, 100)  # height * width * batch_size
        self.fc2 = nn.Linear(100, 1)

    def forward(self, x):
        x = self.max_pool(f.relu(self.conv1(x)))
        x = self.avg_pool(f.relu(self.conv2(x)))
        x = x.view(-1, 64 * 64 * 32)
        x = f.relu(self.fc1(x))
        x = f.relu(self.fc2(x))
        x = f.sigmoid(x)
        return x