Guys ive got a huge problem, ive got rejected by the border police

in a nutshell my plan was spending one day in pristina then go for belgrade, but although I have a turkish passport, (which i can enter all balkan countries without a visa) the border police of the serbia rejected my enterence. Ive got all the documents like my hotel reservation or flight ticket to turn back, i dont know what to do. now im open all the advice.and need help asap