Question for ladies concerning periods?

Hallo :) I was just wondering what it felt like when you were on your period. I mean what it feels like in the vaginal region, does it feel weak? Do you know when things are happening down there/can you feel it? I'm wondering this because I was with my gf yesterday and things got a bit frisky and I got hands on with her... After like 10seconds she asked me to stop because she had only finished her period 1 day ago... What would she be feeling if it was only 1 day ago andshe was being touched etc?