It could just be his natural coloring, which can change as they grow.
See that white stripe (2nd pic) running from his nostril & under his eye? Mine has that on both sides, and some white mottling marks along his lips. He didn't have either as a baby. He does tend to get a little stuck shed on those stripes and around his lips. I can't tell if that's what yours has, but it doesn't look to me like anything to be concerned about.
Maybe just keep an eye on it, and take additional pics to compare later. :wink: