Like Robert said, I think what counts is the big picture at the end of the day. You could drive yourself
trying to perfectly balance every meal.
I try to eat some protein at each meal simply because protein is what keeps me full the longest -- and I hate being hungry! An all-carb meal - like only fruit - would have me gnawing my arm off two hours later.
Some of my meals are protein only, like a shake, but most have some carb with the protein, whether it's fruit, veggie, or some kind of starchy complex carb.
I think of yogurt as being pretty much a carb (due to the milk sugars), but it's going to vary a lot from brand to brand and whether it has sugar or fruit added and if it's FF or 2% or whatever.