Need advice

Hi, I am 23 weeks pregnant with twin boys. This is my 4th pregnancy and totally taking its toll on me. I hurt very bad. I cant move about like normal. I feel as if i am 7 or 8 months along already. Anywho.... im a nurse for a pediatric chome health agency and currently working one 12 hr shift a week... obviously, not enough to take care of my family and bills.... i applied for a nursing home job and they need weekend doubles so id be there Saturday and Sunday from 6a-10p.... 16 hours.... I keep telling myself, its only two days a week.... but i honestly dont thinknI can handle it... my so doesnt work much, he does sales. We are struggling. I have help from my grandpa, but im sick and tired of askong for it because in return, he treats me like im 17... im 25, with 3 kids and 2 on the way. I have to take so to work 35 miles away to and from and since he puts gas in my car, my grandpa, he always asks me where im going, when ill be home, so on so forth. I have extreme anxiety about money and not making it. I know after the babies are born, i can go back to working ft as a nurse and make more than enough. But right now, im afraid of working that hard... im afraid of preterm labor since they're twins... im afraid of hurting....what would you do????