If the lab tested for that, you can forget it. MH never causes disease in men; it carried normally in both men's
and women's genital tracts. Like UU, few STD experts ever test for it.
Does any of this matter? Maybe not. All NGU should be treated, and probably you were prescribed an antibiotic. If so, and if your symptoms clear up, that's all that matters. However, if you have M genitalium and your symptoms don't clear up, you might need additional treatment.