Topping question

DJsmokz310

New Member
Hey quick question here I have a 3 week old seedling & I was trying to top it on fourth set growing in and I cut the whole stem off one of the third and that's the biggest healthiest set of leaves so far. This is my first plant so it must be stressed from my mistakes will it kill the plant or cause it to stop growing?? also its yellowing and turning pale from the bottom up.
 
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