I had the same problem with one of my guinea pigs, Rodney. Buster is just scared. I had to take it really slow with rodney. I just quietly talked to him, gently pet him, and hand-fed him carrots until he got to know me better. I didn't have as much trouble with my other guinea pig,Bear because i got him when he was a little older and going to a new home didn't come as quite a shock. Good luck with Buster