The seedling fell because It stretched too much in search of light. After you transplant cover the extra stem with soil and all good. For next grow keep the seedling closer to the light source just being careful to not keep It too close it could burn the seedling.
my god ...your watering it and its still wet... hahaha ok...You know that plants that stretch ...are over watered right?...You need to wait till its completely dry ! ... Gl in you next grows that plant is dead sorry!