I got a softlock where if you don't buy steroids the moment you can get them, and beat the gym in that town, the store stops selling steroids, and sells the repel items instead. I only know of this because I went all the way through to the city where that lady tries to "save" the Pikachu, and it cannot be selected. You probably should have left ways to keep obtaining the steroids, in order to prevent that (unfortunately all too common) lock. Also, one last thing, is the Mystery Gift functional in this game? I saw that we could fill out the survey in one of the stores, and it unlocked Mystery Gift.