Hi! I completely disagree with people who say that watching movies or shows in your target language is a waste of time. In fact I think that's very helpful to improve your listening and to get used to the language speed that you will find when you talk with natives.
Imagine that you know well the grammar rules and you can also write correctly but you are in a real conversation and you can't understand what people are telling you. That would be very frustrating! Believe me, I know well what I'm talking about. For this reason you have to listen to natives speaking fluently and watching films is an excellent way of doing it (I recommend with subtitles in your target language as well). At least, that's what I'm doing every day and I've to say that now I can understand much more than before.