What would happen if I got pregnant 3 months after a c-section?

I’m almost 4 months postpartum (our second baby) . I had a traumatizing emergency c-section. My husband & I finally had sex for the first time 2 days ago. I’m paranoid I’ll get pregnant again. What would happen? Would my uterus erupt? Would I have to get a medical abortion? (I would never have an abortion unless medically necessary) or would I just be high risk?