Hi, Welcome to HCM. I understand your concern. Sexual urges at this age is natural because of abundance of sex hormones. But at the same time you must exercise control over the impulse. Visiting prostitute or having sex with strangers is a high risk behavior. Masturbation is far safer. Sex can be enjoyed in relaxed mind. If mind is preoccupied with some fear/worries (fear of being spotted or caught by police in your case) it causes sympathetic stimulation that may cause poor/no erection and premature ejaculation. Exactly this has happened with you. There is nothing seriously wrong and your performance will be normal in suitable condition. Relax yourself. I wish you all the best.