Me, my husband, 1 yr old & 4 yr old had flu shots on 9/21. friend told me we got them too early and wont be protected later in season. is this true?

Old wives tale: You should get the seasonal flu vaccine as soon as it is available. It takes 2 wks or so to generate protective antibodies. Once you get it, the protection to the vaccine flu strains lasts for years. The CDC/WHO pick the 4 most common flu strains circulating the globe for the vaccine (more would weaken it). If you are exposed to a different strain it won't protect as much, but it is what we have.