MacBook Air M1 gives average 6 hrs battery time only, is It okay?

It's been 2 months I'm using MacBook Air m1 base variant. In first month it was giving me average 14 hrs but suddenly it becomes 6,7 hrs.

I was using Vscode, docker, postman, Spotify, chrome at a time for development, I thought it is due to this but I checked with Amy friends they were also using the same softwares or few them more heavy softwares.

I tested by watching movies, doing simple work, closing heavy usage but it give 7 hrs max.

I read all the articles and also checked apple official claim that 16 hrs is the average battery timing for MacBook Air M1 2020.