New to this

I tried to make my own vegetable broth with my veggie scraps like i had seen in a few videos but mine is nasty. Like the flavor is just not pleasant, what did i do wrong?

I saved all my scrap in the freezer over the course of maybe a month, filled up my pot with water, brought it to a boil and then let it simmer for several hours other than the scrap all i added was salt and pepper.

any tips or comments are appreciated (: