Feeling sexual attraction to a seventeen-year-old is not pedophilia. It is ephebophilia (interest in mid to late adolescents, aged 15 to 19). Interest in pubescent children aged 11 to 14 is called hebephilia. Pedophiles are into kids between 0 and 10 years of age.
The age of consent is what matters here legally. In some countries it is 16 and in others it may be 14. Soliciting underage prostitutes is always a crime.