I need $13 000.00 to pay a debt that must be paid by next week. Can anyone offer any words of advice?

I am so worried, I must aculate $13 000.00 as soon as possible. The main problem that I have is that I am already in deep debt with student loans approximately $50 000.00 in which I am behind on payments. I have not been working for a year yet since graduating Grad school, and my pay right now is just terrible. I am about to start a part time job next week teaching, which will help me out tremendously. The problem now is that I absolutely need to come up with the $13 000.00 now. I am so worried that I cannot sleep. I am not an American citizen nor do I live in the US. I do have some collateral which is some land that my father left to me and my sister, so I cannot sell. I am open to hear any idea or suggestions. I am so screwed up now that I cannot think straight. I tried asking friends and family but no one can or is trying to help! I feel like I am going to have a nervous breakdown because my back is against a wall. Thanks!