Neither of those jokes...were funny. At all. Not even in an objective, best hopes...kinda way.
Try moma jokes; people can at least relate to those. For instance:
Your mama got so many stretch marks that she's gotta screw her underwear on.
Or:
Your mama got 3 teeth: one in her mouth and two in her pocket.
Or:
Your mamas so damn fat that when I walked around her, I got lost.
Juss tryn to help ya generate ideas
Kabol