Did I pass fetal tissue?

I had my first prenatal appointment yesterday at 10 weeks and 1 day, and the heart was beating strong and I could see my baby moving around on the ultrasound. The doctors told me it was a healthy baby. I went to pee in a public toilet a few hours later, and I just glanced and saw that someone had used it before me, but I didn't care, because I had to pee. When I looked down, I saw strange yellow/whitish flakes. I don't know if I passed them, or if someone had perhaps dumped cereal in the toilet or something? (I live in a dorm, it's not totally, uncommon, lol). My doctor's office is closed for the weekend, so I can't call them, but I didn't experience any pain or bleeding. Is this anything to worry about? Especially considering it was a mere few hours after my baby was deemed healthy? I'm really worried, but I've been worrying about everything lately.