Who’s has had a preemie due to a placental abruption?

I had my son at 33 weeks because of a placental abruption I talked to my doctor asked if that could happen again and she just said to keep in mind that I had one so does that mean I can have this baby early? How many have had one delivered a premature baby and had a full term baby later on without getting shots? I’m 21 weeks pregnant as of today.