If you're talking about the krausen, yes it's normal. It can look like all kinds of things, like bubbles, mats, or pancake mix. If it's been 16 days take a hydrometer reading and see if it's done. It probably is.
Secondaries aren't necessary for making good beer. It's best use is if you need to clear your primary for another batch to get started (recommended) or it's something that needs to age a long time, say for a few months.