What Causes Ribcage And Cervical Area Pain With Sudden Weight Loss?

Hi, may I ask, im 20 years old around 5ft7 was 10st in size 10-12 within 2 weeks ive droped to a size 8 ive had pains in my right side under my ribs going down towards cervix area very tender, hard to wake up always tired, weight loss back ache joint pains vomiting dizzy sweating blurr vision over a year can xou help