I am grocery shopping on my own for the first time these days, now that I can drive, and I've discovered you can wander around a grocery store for a LONG time if you're not careful, looking for what you want to buy. In fact, they're designed that way.
Which is fine, if that's what you have time for - Target is always good for a half hour.
But if you want to get in and get out, try making a list, and put the things on your list together if they're in the same area: dairy with dairy, etc. And better get a basket, because there's a lot of stuff to try.
