Why do I get chest pains after drinking soy milk?

I really cannot handle drinking regular milk, my stomach always hurts. So I switched to soy milk and I’ve been drinking that for a couple of months. But now I noticed that shortly after I drink soy I get sharp chest pains. Why is this?
No I don’t think it’s heartburn, it’s a different kind of pain. Usually heartburn lingers awhile for me but with the sharp pains it’s only for a couple of seconds and then it goes away. But when it occurs it hurts.