Is it okay for a 19 yo to date a 17 year old???

Im 19 and a half ish years old and I graduated just over a year ago. A mutual friend connected me to her friend(we will call her sally.) Sally is 17 and going into her senior year. I did the math and we have about 2 years and 3 months. Is this okay? I’ve been told by mostly everyone that it’s not bad, but I’m getting mixed opinions when it comes to me graduating a year ago and her graduating this year.