Implantation Bleeding?

So, I just got off bc on Tuesday. We BD on Friday and this morning. I went to the bathroom this afternoon and saw very very pale pink floating in the toilet. I took a piece of toilet paper to pick it up to get a closer look and it was very string/ sticky. Could this be implantation bleeding? I know it's way super early before testing if I'm pregnant. My period is supposed to start the 19th so it's a little too early for it to be period blood- I think??