What does this mean???

I been having this for almost 3 weeks I’m going into my 38wk of being pregnant. I’m gonna call my doctor in the morning. The color jus changed today it was mostly pale yellow but now it has a brownish/pink color to it. Sometimes it’s a little and other times it’s a lot. What does it mean?? Im not itching or irritated in that area and sometimes the discharge comes and it goes. Sometimes it’s more and sometimes it’s less but it’s odorless im genuinely lost and confused. .