preemie babies.

so a little background. I am on my 4th baby and my 11nth pregnancy. my first was born a day after her due date my middle was born at 36 weeks after I had preterm at 27 weeks my youngest was born at 34 after in started preterm at 23 weeks. now this baby started labor at 16 weeks. they have me on 17p I am almost 21 weeks so I have had 5 shots. after yesterday's shots I started having contractions again. they want me to come in to get checked. I am worried. the contractions haven't been regular but they are steady and some are very strong. does anyone have any encouraging stories of their preemies to help me be more confident if he comes early? Its very scary for me after my cousin lost her baby at 19 weeks.