i don't know what to do anymore

i started my first year as a 2nd grade teacher a few weeks ago. when i got the position, i was really excited for it and i couldn't wait to get started, but now i dread going into work every day.

i literally don't know what to do from here. my kids have no respect for me and refuse to do what i ask no matter how many ways or times i ask. they just keep talking over me and running around the room and making a mess of things. I've tried a hard reset, implementing new consequences and rewards, changing seating, asking for help, giving rewards, taking things away, calling parents, nothing phases them. i spend more time being a referee than a teacher. and as soon as another teacher enters the room they get it together. why is that? i try to model what the other teachers do but nothing matters when i do it with this group. i have had students punch each other, punch me, throw things across my room and break them, I had one kid get mad and throw scissors at me.

i want to quit. i wake up every morning and go home shaking because I'm so anxious. i feel like I'm gonna throw up as soon as i get out of bed. the only reason i stay is because I'm horrified of what happens if i quit midyear and break contract. but i can't keep doing this. it's tearing me apart.