When I first got my BP he was nervous like you described. If I moved too fast he would jump and pull his head away and would either freeze up or try to move away from me however he could. I found that moving slowly and gently when handling him helped him gradually learn that I am not a threat to him. I think that being quiet when I handled him at first helped too. Slow, quiet, calm and fairly frequent interactions and he got used to me and became relaxed and inquisitive. His age also made a difference for sure like other posters have said.