Comb and wattle development - growth and color - does happen sooner with cockerels than with pullets, but even at six weeks cockerel can go unnoticed, especially to eyes that are new to the game of spotting gender tells. If you post a photo of your bird we can help you sort through things and determine gender.
Good news - not a cockerel -- also not a NHR. That looks like a red sex link pullet to me, but a nice side shot would help confirm that ID.
ETA - the comb/wattle growth is not all that significant and it is still pale and yellow -- now, were it bright pink/red and this bird was not a sex link (sex links are color ID'd for gender, so that eliminates confusion for this specific bird) there would be reason for concern.
We've had her since she was a chick, she was a classic little fuzzy yellow thing, not red at all. She has been developing just like a NHR, she has some black feathers coming out, right where they should.
We got her from a feed store, which ordered specific breeds from a hatchery.