If you're still a beginner and have been training consistently for less than a year, then stop obsessing over the details. Instead, place all of your focus on the most basic and obvious issues at hand.
That's right; forget about the nitty-gritty details of whether your biceps match your triceps or whether your chest is on par with your back. These are issues that you can worry about later on, but until you've thickened up your entire body as a whole to a significant degree, it's simply not worth worrying about.
