Fuller breasts and uterine cramping

love

In Jan 3, i went to go get my pap, blood work, a blood pregnancy test. Everything was fine and i wasn’t pregnant. So maybe about a week ago I started to notice my breasts have been fuller. Yesterday, While I was in the shower I thought I saw something coming out. I squeezed my left breast and thick yellow started coming out, similar to colostrum. I kept squeezing and sometimes it was clear sometimes thick and yellow. No smell. My nipples are not dimpling. For the past couple of weeks I’ve also had uterine cramping worse than before and without my period. I’m supposed to start my period in 9 days. My significant other and I have not been using protection. I barley got on the nuva ring two days ago and I took a pregnancy test yesterday and it was negative. Not sure what’s going on.