how long does it take to get over a ex??

I'm still so broken over a breakup I can NOT stop thinking about him, all throughout my classes I think of him, when I see him in the halls my heart beats so fast and I get anxiety like a bitch. I just want this sadness and pain to end 😫 I'm suffering and he's okay :( what can I do to speed it up? I'm so tired of being sad 😫