Yes for both resnet 18 and 50 the curve was the same.
I looked into my training data,apparently there is a class imbalance,with 600 samples belonging to class 1 and 400 belonging to class 2.Does that impact the learning process,also I am not sure why the training curve is coming out to be flat.
Here is another image corresponding to training on another model with dropout and weight decay and early stopping.

download (1)712×568 14 KB

the final result after training for 17 epochs
[17/50] train_loss: 0.24435 valid_loss: 1.98771

Furthermore,it seems that my dataset doesn’t have any variations in it.