After missing two weeks of birth control shot does it still work effectively when i get it like a day or two after?

I would not count on the shot as post-exposure birth control. It works by preventing egg release and if the 2-week delay led to an egg release, it could bring a surprise. However, many on the shots don't return to baseline fertility for an extended period after stopping. Using a backup form of BC for 2 weeks after restarting may be needed if pregnancy would be a problem.