I was using a public restroom, and I noticed there was a thumbnail-sized stain of something bright red (maybe blood?) at the bottom of the toilet (under the water, near the toilet's hole). I should have flushed it first, but the water was otherwise clear and I thought the stain wouldn't go away anyway, nor would water splash on me. I peed first and then pooped. The problem is, when I pooped, a little bit of water splashed up on me. When I flushed everything, the stain was gone.
If the stain in the toilet was blood, and it had a bacterial STD or virus (HIV) did it seep into the water? Or did the coldness of the water and the chemicals in my urine kill it? I'm so scared I have an STD from this splash of water from the toilet. Please help.