Lena Dunham -- Nodding Head No, Really Means Yes Over Justin Bieber Song

Lena Dunham is eating her words ... saying she doesn't have an issue with Justin Bieber despite dissing his new single, "What Do You Mean?"

The "Girls" star put Bieb's track on blast for its refrain: "What do you mean? When you nod your head yes But you wanna say no..."

It seems Dunham interpreted the lyrics as a rape excuse ...

People jumped all over Dunham. One person scoffed, "Ha, there's literally no vice versa in Justin's song. What he sings is completely inoffensive. Don't try tie this to no means no." Another called Dunham out by dredging up the controversy with her sister: "Wow this is such a hypocritical tweet coming from you."

Dunham seems to have walked it back with a side-by-side comparison of her and Bieber, because nothing says "I'm sorry" like a similar haircut.