What’s the difference again?

I was never really taught what Cum and Discharge was. I live in a ultra conservative area. I hate it! Know one talks about that sort of stuff cause they assume that I don’t need to know until marriage. I’m having health class soon in school but my school district is just as conservative so I don’t believe they’ll actually tell me anything. Can you explain it to me since I think I’ve been cumming. I’m not exactly sure. Can you help me?