I agree. Since I quit I can smell a smoker within being 3 feet of them. And I'm certain that your husband could smell it on your breath, hair, and clothing. Probably your kids, too. It's just that no one said anything to you - don't be fooled to think no one knew.
Some new vapors take some getting used to
vaping an e-cigarette. It's really NOT smoking. It's not smoke. It's vapor. There is no burning or combustion of dried
tobacco going on, so no tell-tale odors. You might end up smelling like bubble gum, gummy bears, mango or peach depending upon the flavors you vape, but that's far better than the rancid smell of cigarette butts.
Your husband being supportive is not surprising, but your son's reaction is. Should it ever come up in discussion, explain how difficult it can be to quit cold turkey without a nicotine alternative. You can tell him the the liquids can be purchased with differing nicotine concentrations so that you can wean yourself off of the nicotine, and eventually just vape zero-nicotine flavors, or stop
vaping altogether if you get to that point.
E-cigarettes have been getting more exposure as an alternative to smoking, and public acceptance will rise as Big Tobacco begins their advertising campaigns on television ads.