I think it will explained somehow on why she got those powers all of the sudden.
Or perhaps she had it all along and bluffed the whole time.

Anyway that's how a cliffhanger works.
... And damn it certainly worked here.

Da fuq happened Kelly?!

So that's why she got superpowers out of nowhere, ok fine, no background no real explanation, it just come in the package like beauty and the like, wathever.

However! superman got his superpowers just with a change of environment when he emigrated from Kiptron to Earth, he even had to regulate his force, heat vision and other powers that made him an entity superior to other men, and while is true that Goku has to train for practically his whole life to become the god-like entity that we known as Goku, he was already inherently more powerful than everyone else, thanks to his status as a Saiyan (and lets not even mention the moon here!), this is even more true for his sons who are even more gifted than his father, with the only things missing being training and experience.

So no, character like Goku or superman being born weak is a load of bs, Kelsey go home you are drunk.