GI problems - watery stool and vomiting

I am a 26 yr old latino male. I have been suffering explosive diarrhea for the past couple of weeks which has led to rapid weight loss (about 35-40 lbs in two weeks). Yesterday, after the diarrhea subsided for about a day, I began vomiting once every hour or so, and the diarrhea has resumed. Cultures were ran for the stool and they came back negative. At first, the vomiting had food in it, but after the first, all subsequent releases were a dark green liquid. All vomit produced since the first yields several ounces of this liquid (bile perhaps). What should I do?

[Twilight_Princess]

Do you think you could have food poisoning? You need to see a doctor ASAP. Vomiting and diarrhea like you are having will cause you to dehydrate and you should try, if possible, to take small sips of liquid with nutrients in it in case you are dehydrated. Have you been seeing a doctor for this?

[Elevithian]

35-40 lbs in 2 weeks?  IMO that is a medical emergency and you need to see a doctor PROMPTLY.

[Twilight_Princess]

Curious to know if you seen a doctor yet and how you are doing? I didn't want to scare you, but that amount of weight loss is VERY concerning.

[gims]

my nephew of 12 years old has been vomiting and having diarrhea for months now, he is always coming back early from school because of this. the doctors say that he has nothing and that he must have some stress from school. I dont think its normal to have these symtomps for almost 9 months.. can anyone help please?