i cant really say why u threw up all this long after u smoke first... so i highly doubt it had to do with your bud, rather its more likely its your body's reaction to the weed, perhaps hunger, dehydration or any other chemical reaction of the stuff in your body/belly

it can be almost anything im not a doctor but throwing up can be result of anything u name... u can sit 5 hours straight in front of some old CRT monitor like the one i got here in office and get really drowsy and/or hrow up if u r the lcd generation and not used to long hours of this thing... or u can just go, stand up in a room and free-cycle around yourself with arms stretched out, for 10 rounds and see how u will feel afterwards!

my final word: reaction to weed or substance taken in to your body will not give u 2 hours of silence before itself... it will happen almost as fast u get high or a little bit delayed in comparison

and this is the part i truly hate... when u go to lots of doctors/hospitals they tell u or use it in govt statistics that it was weed related incident!