how much stress can it take?

ok i recently got 2 clones which i believe are hasplant (they are about 6-7 inches tall), and not long after planting them (when i bought them they were already rooted, but had some yellow spots on the lower leaves), they got spider mites. I bought some mite spray and the mites seem to be dead now. But like the first 3 sets of leaves on the plants look TERRIBLE the bottom ones are dead (they are brown, yellow, and curled up) and the next few have big yellow spots on them. Also i havent until now been using any ferts so thats also why the leaves are yellow. This question may seem general but.... How much stress like this can a plant take before...

a. it turns hermie
b. it doesnt produce decent buds

thanks..... if the questions to general for a specific answer a ball park would be fine.

p.s. will dead leaves re grow? or repair themselves?

 

lol thanks man that gives me hope. Ill try to get some pics up to show you my poor lil girls