Hi there!
Thank you for calling me over !
Congratulations on your first bake, and make of mother, ! Mine took a couple of attempts as I explained here. And yes, the heaviness is definitely the wholewheat flour. I regularly make rolls - white and brown. The latter are a combination of white and brown flour. The recipe (and story, of course), is here.
My mother is now nearly 6 years old and between bakes, lives in the fridge. I fish her out on a Thursday morning or when I need to feed her - usually about 3 to 5 hours before making the dough - which depends on the weather (temperature). And yes, 6 years later, I'm still learning.
Good luck with your sourdough journey!
RE: My first sourdough