Rhogam shot & spotting

Last night when I wiped I noticed a tiny, tiny bit of red spotting. It was like one dot and when I wiped again it was gone. I went in for an ultrasound today and everything was fine with the baby and my cervix was completely closed. I am 24 weeks tomorrow. I am unfortunately Rh negative and I was wondering if I would need the rhogam shot. I asked my doctor about it a few months ago when I found out I was pregnant and she and her nurse said only if there was trauma would I need the shot before 27 weeks. Everywhere I read online on discussions women said their doctor said they needed the shot for any type of spotting no matter how minimal or what color. I don’t want to bother my doctor because the last time I talked to her nurse about the spotting she was acting like it’s no big deal and kind of made me feel like I was being a bother, maybe I’m just too sensitive. Has anyone else had this issue and needed the shot? I don’t want to harm my baby and I also want to be able to have children in the future. I’m just really scared and don’t know what to do. I love my doctor but I hate that my nurse has made me feel as if I’m a bother