Teaching is hard

This is my first week of teaching, and also doing my 20-hr a week retail job. I thought I would teach 20 hrs a week, but so far I have 12 hrs, and I'm overwhelmed by lesson planning and keeping track of my students and their progress. I have 19 students, though some of them are in group lessons. I did the math, and I will JUST get by on this salary. Anybody got a fool-proof money-making scheme? I had hoped to save up some money this year! Should I bite the bullet and try to take on more lessons?