Foul gas pls read

J

My son is 1 year 2 months old. Lately as of about 2/3 weeks I've noticed he has very very VERY foul smelling gas. I'm not exaggerating. It smells like a grown man took a dump. He is still mostly breastfed will eat food here and there but doesn't have interest in it yet. I have no idea if that's normal. But now I'm feeling kind of worried. I have to wait til Monday to schedule an appointment. I thought it'd go away on its own but it hasn't. He's very gassy and doesn't go poop every day like he used to. But he's not fussy either. He seems fine /normal. Anyone have any insight ?