Pregnancy Regrets?

After my first child it was difficult to get pregnant again. But When we found out we were having twins, one of my options was to terminate the pregnancy. I always said I wanted 1-2max. My first year with my high need baby was really hard on me. I’m now 24 weeks along and I try to talk myself that I’m going to be fine postpartum but I’m afraid, afraid of PPD and with 3 kids going to sink deep. Anyone feeling the anxiety ? Am I being ungrateful?