Here are the lyrics you mentioned with the full chorus added:
If I asked you to stay just a little bit longer
Would you pack up and go?
Or would you tell me you'd rather stay here
'Til the sun down tomorrow
I knew better but you said forever
Now you're just making me wetter
Love on the brain
Got love on the brain
Boy, you're playing dirty like my name ain't worth a thing
Yeah, my mama told me I don't play your games
But I can't stop, and I won't stop
I don't wanna lie
My momma told me not to let 'em hold me down
Don't wanna live my life like a ghost without you
Don't wanna give up, no way
Just a little love, just a little love
Love on the brain
Got love on the brain
Boy, you're playing dirty like my name ain't worth a thing
Yeah, my mama told me I don't play your games
But I can't stop, and I won't stop
I can't stop, and I won't stop
I knew better but you said forever
Now you're just making me wetter