Accept the peaks and valleys!
Two steps forward, one step backwards.
That's the way language learning frequently goes. You cannot expect your progress to follow a straight line up to the moon. You're going to find that sometimes you seem to "hit the wall." You'll make great progress for a few weeks and then suddenly you may find yourself really struggling. No matter what you do, it seems that you can't make progress.
Be prepared for this. It happens to everybody.
The good news is that it won't last long. Just stick with it and try not to push too hard. Go back and review things you already know. Don't try to force the learning of new material. All you have to do is to stick with it and don't give up. Before you know it, you'll make a breakthrough and you will have achieved a whole new level of competency!