What should I do if my pepper plants got too strong of fertilizer and they are wilting?

Question

Basically, I added too much fertilizer to my pepper plants unknowingly. I thought it would help them, but the ends of the pepper plants are starting to turn brown and their stems are weak. Also, one of them is wilting. I have three types (Chile Cayenne, Marconi, and Big Thai Hybrid). I was wondering if I should give them potassium, as that might help them. I need to get them outside in a month in my garden. I am trying to be patient with it, and see if the problem goes away but I don't see anything helping the matter at hand. I was wondering if there's anything that can help them? I have the pepper plants under grow lights in my room, and it gets bright in here.