White stuff in pee.Could I be pregnant?

Chelsea

Hi ladies

I have been ttc and I got a light period with symptoms including heavy breasts, back pain and cramping that wont go away. I took 3 pregnancy test and all negative. I have noticed over the past few days that I have some white strings that sink to the bottom of the toilet but nothing when I wipe. Im still having sore nips and cramping in my lower stomach.

Any ideas of what this could be?