My Grand daughter got her period?

My fourteen-year-old grand daugher is staying at my house this weekend, and I think that she is having her period. She keeps going to the bathroom and has been using quite a lot of toilet paper. About an hour ago, I noticed that there was some toilet paper with blood on it in the trashcan. She has also been clutching at her tummy as though she is cramping. I know this isn't her first time, because about 4 months ago I was at her house and noticed wrappers from pads and tampons in her bathroom trashcan. Her mother had a hysterectomy 9 years ago, and my grand daugher is an only child, so I know that they belonged to her. There were too many in there to belong to someone who had just spent the night. Anyway, I think she just must've got caught unprepared this time. Obviously, she's in pain right now and is probably embarred. I know it's so awkward to talk about periods at that age, especially with your grandmother. I want to help her, but I'm not sure how to approach her. She and I are pretty close, but this subject has never came up before. Should I just ask her if she's having her period? Or should I run to the store and pick up some pads and Midol and leave them in the bathroom for her? I want her to feel like she can talk to me about this.