Age difference, 15 year old guy 12 year old girl?

hey, i got a problem, there's a girl i like and she likes me, problem is she appears to be older than she really is, im 15 and i thought she was older but she is actually 12, but soon ill be 16 and she will be 13, and with me being an adult wont that mean im breaking the law by being a child molester? and what can we do together legally? when i met her she seemed more like 14 years old not 12, but i really dont no what to do