I need a pick me up.

15 weeks pregnant today. I'm 37 and I have 2 beautiful children who are 20 and 18 form a previous martiage. I have had 4 miscarriages and had been ttc for years. My SO has 2 girls from a previous relationship. Im beyond excited to be expanding or happy family. Last week I started very slight spotting and doc sent me to bed for 2 days, but only did an ultrasound to see that baby was ok. 2 days later back at work more spotting. Back to the doctors. This time he tells me it's "preterm labor", I'm "high risk" as I have lupus. He wants to start Makena injections next week and sent me back to bed for the weekend. We did find out we are having a baby boy! Doc was saying all this stuff about "age of viability" and "bed rest". I am so scared! I am the major bread winner of the family and scared how we will make ends meet if I have to stay on bed rest. I'm terrified of losing my beautiful baby boy. I feel like a failure.