What Would Cause Vomit To Smell Like Burnt Hair? I

What would cause vomit to smell like burnt hair? I woke up yesterday with loose stool that quickly turned into diarrhea. I only threw up one time. I have been diagnosed with IBS and can't spell the other 10 years ago, so I am use to the loose stools but this has gone on for day and 1/2 so I figure a flu. What bothers me is the smell of my vomit. Was to see my Dr. today but they cancelled. Was told 3 weeks ago that I had to change eating habits b/c numbers from being diabetic. That is what the appt was for. Too see how I am doing with new blood work in 2months. Is this a sign that I am? Or just some fluke?