Did you feel this way as a new teacher?

First year, teaching K. It’s only 3 1/2 weeks into school but I feel like they aren’t learning anything. I know I’m probably wrong; it’s just how I’m feeling lately. Sure, they’re learning procedures and how to behave in a school setting, but I am concerned with the academic aspect. My low ones who demonstrated from the get-go that they knew nothing still seem to know nothing. Like I cannot teach letter recognition! I can expose them over and over, in different ways, but that’s all. Again it’s early, but I just want to be the best teacher I can for them!