It a little hard to see the textures you are using but it looks like you have two problems.
- First there is the Black which is is the background of of your diffuse texture being pulled over into the model buy the bump offset. To solve this you just need to pad your UV more, by texturing further outside of the UVs.
-the models texture also appears to oddly distorted created jagged bits. The usual cause for this is the height map being to noisy or does not match up perfectly with the diffuse texture.