Trying for no 2 - been 8 months

Samantha
We really battling to have baby no 2, our son just appeared and we were so excited, then I nearly lost him at 8 weeks then at 22 weeks, he came early at 32 weeks! His defiantly out miracle, I want baby no 2 but beyond scared to be pregnant again. I take maternal calcium everyday to help but still no baby!