Using a loop to predict longer vectors with a LSTM
I'm going to answer to myself since I managed to fix that issue. The problem is that my model was overfitting waaaay too much and I had to add a dropout between each layer.

Now the result is better :



I will now re-tune my model and improve it a bit.

note to myself : don't be lazy Julien, plot the validation loss next time

EDIT :

I trained it during 36 mn with more neurons per layer. Without overfitting, it's way way better.



Now I can predict 8 days of datapoints with a better accuracy.