well, its somewhat overwatered now. possibly a bad idea to flush more.
looks like you shouldnt have worried so much either.
looks just a tad overnuted, not enough to worry about.
i woulda just skipped the nutes next or maybe just a half dose.
basically if you see that nuteburn, it means you are feeding maybe 101-110% too much, need to back down that 1-10% next time.
hows the drainage? overwatering like that usually only happens with poor drainage.
unless, it was droopy like that, before the flush, then its possibly just fucked.