She dumb as fuck playing cards, if the best hand she had was 10 high after a draw, that means she threw away an Ace (the highest card) instead of a 10 for some reason, if she kept the 5, 6, 7 hoping for a straight that was also kinda dumb cause if she believed he wasn't bluffing then he would've had to have a straight or better to not draw any cards meaning a possibly 9 high straight wouldn't be too good compared to what she believed he could have. (apologies for no periods, this was just a long winded random rant) Also, despite her drawing one in the manga more than one card has changed out of her hand.