keep flushing it for the next week, or when you see new leafs thrive looking pale light green. Thats the only thing that you can do for nute overdose.
I suggest you use organic fert. Organic fert wont burn your plant and it have most of the micro nute, such as calcium,zinc,magnisium the most important nute during vegetation stage. Try this fert from terracycle. it is worm poop! I have had great results with it. you can use it right out of the bottle without mixing it. I only use this nute during the first 6 weeks from seed. Then i switch to pure blend pro veg. it is a little stronger. Here is couple of my plants at 13 days old using wormpoop.