These are probably not chest pains but pressure pains from the baby pushing up towards your chest area. If it is not go to the emergency room asap to get this checked out.
Chest pains can be caused by heart burn. This is very common during pregnancy. You may find it helpful to take TUMS or watch what you eat and how often you are eating. Some people find it necessary to sleep with their head elevated, such as in a recliner.
you can get chest pain while being pregnant from alot of things like gas ,indigestion or preasure from your baby or Anemia or asthma or widening of the rib cage and so much more.
Chest pain may be due to gas problem if it is recently developed one. But if itis there after evreytime you vomit then it is to get attention. Consult doctor immediately because this may be a sign of certain problem during delivery. Did you have it before pregnancy? immedialtly check.
This is probably just heartburn, but in any case because your pregnant and are now caring for two - you need to see your doctor just to maybe do an EKG and make sure nothing serious is going on.