its ok!you dont have to be sorry
mollies can live in fresh water but they will live longer in brakish water(water with a little salt in it)
you could get a pair of dwarf gouramis!theyre colourful and small.But two males might fight so i would only get 1 makle and 1 female
how about swordtails platies and guppies?do you like them they can be kept in fresh water with the gourmais