Met a girl on holiday, she looked about 18/19 but shes 15,16 soon.she came over to me and started talking but im 8 in sept what should i do?

She is extreamly beatifil the hottest girl ive ever spoken with let alone has come over to speak to me she is pretty mature for her age another thing that made me think she was older she wanted me to add her on facebook and insta sc etc to stay in tourch because i came home yesterday she lives about 1hr 3/4 drive away from me would it be wrong to continue this due to the age or not what are your opinions i really like her but the age thing is just a growing problem im not sure