Yes, that's very toxic .. im lowkey going through the same thing with my mother best thing is to do is ignore her when she's yelling and say yes ma'am and agree... and she shouldn't comment about your weight bc it doesn't matter what's one the outside its what is on the inside that matters... And for your Grades just do your best you got it trust me just take lots of notes and STUDY!... and ofc you're gonna love your mom she you're mother.... And not everything has to be perfect... I bet you're really pretty and smart and intelligent and you can do anything you put your mind to! I hope things get better in your future
It could be because she stressed or she just had a tough time in her life. Or she just mean and stuff. How about trying to do something for her and see if she becomes friendlier? Make her breakfast, Get an 100% on a test, Give her a hug, Buy her a gift? Anyway Good Luck!