What’s the name of this teen movie?

Hi there

I’m looking for a movie that I saw about 8 years ago. is a teen movie set between the years 1990 and 2010. the main girl has short black hair and always wears red lipstick. she gets a boyfriend who has wavy hair.

In one of the scenes the protagonist is walking in the street and meets a friend with whom she disputed before and who is eating something, then the friend threw her food on the ground out of anger.

in another scene the protagonist sees her boyfriend kissing another girl at a party.

It’s all I remember. I hope you can help me.