Totally agree with
@Loverboy Skyline . I don‘t think she should be weighing any more. She‘s actually big and probably on the high end of the weight chart (that doesn‘t mean that her weight/size isn‘t perfect).
My male English Mastiff was the same weight at 15 weeks and he weighs about 230lbs at 2.5 years old. Not suggesting that Daisy is going to reach that, but I would not at all consider her underweight or anything. She looked great in all the pictures you have posted so far.
Regardless, I wouldn‘t be surprised is she was going to be really big as an adult