Makena shot!?!

I’m currently 35w2d and have been getting Makena shots since 16w and got my last shot 34w5d I still have one more left and this would technically be my last but I just don’t feel the need to take it I get a huge rash and have left pain in my arm not only that but the big thing is one side effect it’s very very small but is stillbirth I feel at this point baby is good and I just feel more comfortable without it, just wondering how long did you go into labor after the last dose of Makena, doctor wants me to do one more shot but I have the right to refuse it right?