Is that FF Ocean Forest? If the soil is too hot the seedling can struggle for
a while. Maturity will slow, growth will slow and your plant will just look sick for a while (1-3 weeks or so). I personally have had a 50/50 success rate using bagseed (bs)where half showed no problems and the other half did. My TW didn't have any problems at all. I'd let your plant dry out a bit first until the pot feels
light before watering again
. If in 3 days from that point she is still sickly get some seedling soil to save yourself the hassle then transplant after 10 days give or take. If your short on cash I've had good results growing seedlings in Scotts topsoil that had been sifted to remove ALL large pieces - using a kitchen strainer. The end result is a fine, fluffy low nutrient grow medium. Good luck.