This might be a little gross, just warning you now!

A few years ago I was going through a really bad time emotionally, I was having a lot of flip outs and a breakdown. I tried to get a job, but the night before I was meant to start I panicked and flipped, I just couldn't do it. I cried so much that I ended up being sick.
The problem now is- ever since then, I throw up every time I cry. If someone yelled at me, if I'm feeling miserable, whatever reason, I throw up, and it's just a little embarrassing. I can just feel my stomach churn and I have to run for the bathroom. I don't usually throw up so much a wretch, but it still isn't nice.

WHY does this keep happening, is it anything to do with my PTSD, is crying a trigger for me or is it something that just happens to me?