So I just had my first anal vibrator experience and it was absolutely eye opening, in both good and bad ways. Number 2 is especially important!

1. After about 30 minutes of stimulation, I started getting what I assume were blood? Secretions. It wasn't super red, more of a brown-reddish color, and I dont think it was poo because there was separate instances of it. I wasn't like bleeding though. Is this normal?

2. When I put the vibrator deep enough, I hit some sort of muscle? Which, when I hit it, I felt extreme pain, so much pain that I felt like stopping right away. I remember feeling this too when I had anal penetration with another guy before. Am I hitting a certain muscle/bone/part of my body? How to avoid hitting this?

3. Any tips on completely emptying your bowels? I thought I did my enema pretty well but there were still bits of poo so...

4. After stimulating your prostate/butt, is it normal to "cum" by peeing? After around an hour of stimulation I started feeling this sensation of wanting to pee instead of wanting to cum, and when I let it out it did feel really good. Is this normal?