You likely have an Undescended Testes
During growth, testes usually descends from the abdomen to the scrotum
.Some times it can get arrested in its path in groin or inside abdomen.
That must be case with you
So get an Ultrasound
scan of the scrotum, groin and abdomen.
If its elsewhere, it has to be removed as the chances of cancer developing in it are 25 times more .
Thanks and Regards