I have bought a new lizard and he was sold as an Eastern Spiny Lizard and I was told he is an agama. However, he looks to me like a collared lizard! He looks almost identical to the one on this link

http://216.109.89.105/reptile_amph/reptile_amph_m/AR0064_3m.jpg

except that the lizard on this link has 'baggy' skin and mine has tight skin and mine also has much bigger, spinier scales. His tail is spiny almost like a croc. And he isn't as spotty as the one in the picture. But apart from that his markings and face are the same. he is quite flat bodied. He likes to climb a lot. He is about 8 inches long. His tail has a blue tinge. His belly is pale. Under certain lights he looks gold. He bites a lot.

Any help would be great, thanks!