Hello, hello, hello from Slovenia @Francesca13! Croeso ar y fforwm! (Welcome to the forum)!
I’m happy to hear you’re enjoying the learning method and you’ve come a long way already. I had the difficulties with “gosip” phrases too but you’ll see … when the Summer comes and you’ll be about comming to Wales you might even long for them to be used. 
It happens that there’s a blockade of some sort and you can’t remember or you forget some things. Mixing things is a very common thing (at least with this method) but at some point it all comes to its place and, yes as @Betterlatethan says… the new wonders and mysteries will appear.
I wish you gather that needed confidence by then to be able to speak Welsh because speaking in the wild (as we say) is priceless and gives you so much of everything: knowledge that you can actually speak, boost to your confidence to sepak more even with strangers and wish of learning more and more.
So Da iawn ti! Keep going the way you started and when there’s a stop and you have questions, don’t hesitate to come on here and put them on. Here’s always someone to help and one of the tutors (@aran and @iestyn) is always on here too and helps their own way. Even if you’re not sure that something is possible and you might be stubborn as I was, @aran will show you that this is not entirely true. Everything is possible even with such a self-beating and stubborn person as I was (umm … well … might be I still am sometimes ).
Oh and if you need some resources or you have problems and questions about “how to” on the forum, you might find this thread useful and helpful.
Now … Welcome to the forum and the community once again and keep posting.
(Oh … and how I started to learn Welsh? I was tackled by rugby and two teens pushed me into scrum with saying I will never manage to learn the language).