Does Miscarriage Affect The Results Of Coombs Test?

I am rh negative and I just found out I am pregnant . I had a Mirana birth control put in a couple weeks ago not knowing that I was pregnant and bled heavy after . Is it possible that I am sensitized now . Also I had a miscarriage less than 3 months ago , is it very possible that that could affect the combs test results , if I was to be tested for sensitization . Last .. Is the combs test always 100 percent accurate . Thank you so much in advance ! I am so worried .