Is your loss not decreasing at all?
If so, you should lower your learning rate, e.g. by dividing by 10 (1e-3, 1e-4, 1e-5).
Also if that doesn’t help, try to normalize your input, e.g. with transforms.Normalize 3.
As a small advice, you should create a Dataset and DataLoader to handle to data loading, pre-processing etc.
You can find a tutorial here 2.