Rubella/German measles during pregnancy

Patient: I am a mother, and am currently pregnant. My son is 2 years old, and was recently with another boy who had German Measles/Rubella while my dad was babysitting him. I am not immune to German Measles/Rubella and am very worried about my unborn baby (currently 34 weeks pregnant) My 2 year old son has had all his vaccinations for Rubella/GM, but I am still worried for my unborn baby, is there anything I can do? Could my dad have carried GM/Rubella back to me when I picked up my son, or anything like that? Thanks in advance.

Symptoms: Nil