Help with nausea

Okay so, I have never ever been so nauseous on my period before. This is the first time I’m experiencing nausea and I can’t deal with it right now because I have to practice for my presentation. On top of this I keep having to run to the bathroom every five minutes and every time I push even slightly I have to stop to gag. I haven’t eaten much today, just some sunflower seeds and a ton of water, plus a bagel and a quesadilla like thing with apples, cheese, and mushrooms. While it’s worth noting I’m lactose, this is nothing like when I eat dairy. I’ve never been nauseous, only just had really bad stomach aches and gas. Please, if you have any methods to help me feel better let me know.