Cutting family planning?

I'm so sad. We always planned on 3 babies, but I'm stuck in a tight spot. We can't afford another baby until i go back and finish my nursing degree and get a job nursing...but pregnancy is so hard on my body that i always end up being put on bed rest by the 2nd trimester. I could hardly do my office job in my first tri with my last baby, with constant er trips and vomiting every literal 15 minutes. So... basically i feel like it just can't happen. I'm crushed. This kind of even ruins my passion for medical care because my specialty has always been prenatal, maternity and birth. But i don't want to spend the rest of my life watching women acheive my dreams and do what i wanted to do. I'm still sad and ashamed that i never had an all natural birth. My last two births were horrible scary experiences. I hate even sharing details about them, but im always trying to help other women have magical happy empowering experiences. I feel like the "always a bridesmaid never a bride". :( feeling an awful lot like my life is a mess.