I had a period my whole first trimester with my first born. i'm wondering if that could happen again?

Yes: Many women have bleeding during pregnancy that is similar to a period. It could happen again

Yes but be careful..: First trimester bleeding is fairly common, particularly in younger women. However, there should never be an ASSUMPTION about the health of the baby based on past experience. Be sure to have an updated Ultrasound and consultation with your OBGYN, and make sure to keep track of any abdominal pain, contractions, recent medications, or other bleeding problems elsewhere. Good luck.