Pain from Watching Porn?

I haven't watched porn in a while but I feel like I've experienced this before. Earlier, I just watched porn and as I'm watching it, my vaginal area starts to hurt. It hurt to move. I used the bathroom and spread my legs to try and ease the pain and I guess that worked, or maybe it's just because it's gotten time to stop or something. Is this normal? Can I stop this? Is this called something?