Should I?

I'm traveling to a different province in about 3 or 2 weeks and staying for a week. Today at my doctors appointment they measured my stomach and said I'm looking around 30 weeks instead of 28 and her head is down. They also said since I'm so small and young I probably won't carry her full term. Should I bring her car seat while I go on vacation? I'm for sure bringing her diaper bag with a few sleepers, diapers, etc. just in case but should I bring her car seat? The vehicle we are traveling has 5 seats. My mom is driving, brother is in front, boyfriend in back, and I will also be in the back. Please answer your opinions!