Daycare situation.. wwyd?

My son does not care for daycare. He’s 3 & just started around the second week of January. He cries every time we drop him off. Well, last week, he came home with bruises on his knee. His dad asked what happened & he said a girl pushed him down. I let it slide. A few nights ago, I asked if he had a good day & he said yeah then went on to say that a boy hit him. I asked why? He said well I hit him too. I said well why did you hit him? Blah blah we had the talk that he doesn’t hit other kids.. but he said this kid hit him in his head. He started crying & told the teacher.. the teacher told him to stop crying. Which really pissed me off. I cried for 30 minutes due to feeling like I just send my kid there & I have to worry about him getting hurt or bullied by other kids & the teachers not doing anything about it. I plan on going up there & having a talk with the director but I’m new to this daycare thing so I’m not sure what steps I should take or how I should bring it up. Any help would be great!!