My friends getting high and i'm upset.?

So, my friend just out of the blue texted me saying "I'm getting high" I've never been aware that he's been high before, but I got upset..? Or angry? I don't know, I have nothing against it really, he can do what he wants but, I'm not sure why it upset me.. I need help >~< as soon as possible please.

You are basically Worried for your Friend because your thinking that something will go horribly wrong to your friend which is totally normal, but maybe you should check up with your friend to let your worryness go's down to make sure he is ok.