Could you name this Beatles song?

This is bothering me...I have a tune from a Beatles song and I don't know which one....it is a love song (doesn't help much, I know) I think John is the main singer, and some of the lyrics are "I love you so" "and of all the things..." "I love you now" there is a repeated melody with six notes.. da dum da da da daaah if that helps any...This is really bothering me thank you so much