Is it unreasonable to be annoyed with my son's teacher

My kindergartener had an issue at school the week before last. It was an issue that lasted a week and a half and his teacher never emailed me about it. She waited until the problem got worse and then called me angry and said his behavior was unacceptable and she was surprised since he's never had a single issue before. I was surprised too because he's always been very well behaved. Well with this unchecked I guess it got worse until she called and kinda exploded on me. I obviously apologized and immediately talked to him and figured out what was going on and he lost some privileges and we made a reward system to try and fix this behavior issue (which we have never had to worry about) I asked her to keep be updated about the behavior so I can address it right away and so i can continue the rewards system and all that. She said she'd call me. She never did. All week she didn't call. I emailed her at the beginning of the week asking how his Monday went and if she could send me a quick update during the week so I am in the loop. She didn't get back to me. I emailed her 2 more times since then at the end of that week and again today and nothing.

I'm trying to do my best as a parent to fix this and I'm getting no communication. Is it unrealistic to expect her to communicate with me at least once after 2 weeks ? Especially if she called me mad ?!