Boistone. Im going to give u my 2 cents, thats all.

First of all ur sprout looks like it is completely stunted (growth wise). Your "day 12" picture looks exactly like your first picture, which means it hasnt done too much in 12 days. Marijuana can be vegetated into a nice sized bush, and ready to flower in 30 days. Ur at 12 and have a sprout.

Never ever give a plant any nutrients in the first 2 weeks of its life. By nutrients i mean things with NPK's, which are the set of 3 numbers, ie - 10-50-20, these NPK ferts. include your "root started" nutes... NO NUTES FOR 2 WEEKS. U should only be using Ph balanced water at around 6.5 for those first 2 weeks, maybee a drop of superthrive for the developing root system.

If i were u i would find a couple more seeds and start a new batch

And dont dorwn them, after they pop out of the dirt u should water them for at least 3 days. Sprouts can drown very easily. What i do is pop the seeds in paper towel, then put the pop'd seeds into pre wet soil in party cups. Dont plant them in soggy soil, just some nice damp soil, this will allow enough moisture for the pop'd seeds to sprout and start to veg for a couple of days. If u really think they need moisture mist them a lil bit w/ Ph'd water.

These plants are exactly 12 days old from a recent grow