Do I really need to create a budget?

To your very simple question, I offer a very simple answer: Maybe you do, maybe you don’t.
Let us explain.
Yes, you need some kind of understanding on what you do—and will—spend money on. But no, you probably don’t need a formal written document.
There are two reasons we say that.
First, if you have a significant other and you are both anal-retentive types, the idea of writing “75 cents for the daily newspaper” and “$5.99 for the lunch combos down at Joe’s” is going to drive one or both of you nuts. Nothing good can come of that.
Second, once you start to budget, you will probably look to hold yourself to some kind of norm -- you will say things like “how much do most people spend for lunch, or on their monthly housing costs” -- and feel guilty if you exceed it.
That doesn’t help you very much, either.
Here’s why. Even if you know the average couple spends about 25% of their gross income on housing, that number is only an average. It does not necessarily apply to you. For some people, having the nicest home they can afford is important, and they’ll push that number to 40% of their income and not blink. Others couldn’t care less about housing. They want to entertain, fund social causes, travel. Whatever. Budgeting to try to correspond to some mythical average is not the way to go.
The best approach is to figure out exactly what you (and your partner, if applicable) want to do and act accordingly. If your goal is to retire with 10 years, figure out what it is going to take to do that, and go from there.