Suggest Treatment For Diarrhea, Vomiting And Extreme Lower Back Pain

i have been puking out mucus and what seemed to be urine at one point all day and i have been pooping completely liquid and my poop looks like vomit. also when i try to rest my lower back is in extreme pain for some reason, this usually happens when i spend a lot of time in bed (the back part). i started the day at 5 am with a rude awakening to pooping and vomiting and have been doing so at least twice per hour since then, can you help me? i weighed 155 lbs yesterday now i weigh 140 lbs.