No, it's not. It's late Middle-Ages and Renaissance with perhaps a few Early Modern elements-not late Early Modern Period. Ie, firearms have not fully supplanted armor and melee by any means and far from every man-at-arms would have one. And at this point, a firearm would be a primary weapon-it would replace a spear or halberd, not be a sidearm, really.

TL:DR No, you don't need a gun by any means.