I get this feeling & don't know what it is?!

so it's kind of hard to explain, but i get it whenever there's something different planned. and either I don't know about it, or I do know about it. it starts in my stomach and it's like a tingly feeling but it goes up my throat, and it makes me feel like I'm about to vomit. I have to stop whatever I'm doing and it kind of makes me feel upset. I have know Idea ! please help? and no stupid answers please.