group strep b

 has anyone else ever been diagnosed with Group Strep B? supposedly my ob found trace of it in my urine. I'm only 13+6. I seriously do not like this office. they waited until this appointment to tell me that I came back positive for GSB. they didn't tell me when they find out. so they're making me do progesterone shot starting at 16 weeks to 36 weeks. should I get a second opinion? with my daughter and son I never had GSB. does it just randomly come? progesterone shots and GSB are 2 different things.  the progesterone is because my sone was born at 28 weeks and my OB was convinced it was preterm labor (even though it was a placental abruption. I'm seeing a different OB than I had with my son because I had an emergency c-section and my old office doesn't see patients after a c-section)