My job is causing serious health problems

Hi everyone! I come from a very poor family and I decided to pursue a masters degree in a different country. I gathered all savings I had, went abroad alone with my own money and found a job. Im currently studying and working at the same time. At first it was ok, but I have been working at my job for a total of 4 months and this last month is unbearable. My shift is supposed to be 6hrs/day from Monday to Friday but I work 8-9 hours a day without getting more money or days off and I have not had a single Sat or Sun off since I started working (they usually give me Mondays or Tuesdays off instead). Sounds bad, right? well, thats not the problem believe it or not. My job is so physically demanding that this last month the ONLY thing I do after work is lie in my bed for around 12-13 hrs until the next day comes. My back hurts so much that I only actually sleep around 4 hrs of all those that Im actually in my bed. I have sleeping disorder, headaches, leg and arm pain and back pain that wont go away no matter what remedy or medicine I take. I eat 3 times as much as I used to eat and I still lost 10 kilos in 4 months. If I keep this job I will never study because obviously I am so weak that I cant even walk. I never see my friends anymore and my relationship with my boyfriend is starting to have problems, even though he does more than enough for me on a daily basis. I seroisly feel I will collapse any minute or even stop breathing. Im looking for a new job, but I dont think I can take the pain for so long until I find one. I want to quit tomorrow but if I do, I only have enough money to survive for 2 months. What do you think I should do?