3 day notice to pay or move out?

I am a day late from my rent since I get paid end of every week. My manager I think has something against me and rudely came with the form labeled "3-DAY NOTICE TO PAY RENT OR MOVE OUT". I got shocked, but I never got a warning. I am in Downey, CA and I am wondering if she is able to to this legally. I mean, shouldn't I get a heads up before getting this notice? I never been late on my rent.