One Cotyledons Fell Off!

Thanks for stopping by

So i was just in my growarea putting things right, i wanted to support the the steam with a straw, so when i put the straw on the steam, as i did this one of the cotyledons fell off

the two cotyledons went yellow before hand and looked as if they dried up!

Will the plant still grow? as ive got around 10 leafs and how come the Cotyledons went yellow in the first place?

Thanks

Could be over watering. Time will tell if it survives.