I thought the way you did at first, thinking it wasn't good to call myself anything like a Christian for example, but I think you can call yourself a Christian if you have repented and believe on Christ because even the Bible refers to the disciples being called Christians----- Acts 11:26--
"And when he had found him, he brought him unto Antioch. And it came to pass, that a whole year they assembled themselves with the church, and taught much people. And the disciples were called Christians first in Antioch."