Hey , so the first thing you need to do is to calm down , nothings going to happen if you fall back or if you aren't improving take some time for yourself and do things that make u happier , take things easily it's not life or death.
And now for artblock advice
If you aren't feeling inspired and you aren't having fun practicing and practicing. Try drawing random things instead , your creativity depends on what you have collected info then applied it , so example I saw a brainless donkey going arround eating apples then walking them. Did that make sense not at all but was it creative hell yeah, creativity is when you get info so get alot of it then use it on drawing whatever you want .