Question for Muslims only?

i have a problem when i am performing salah i was wondering if anyone suffers the same thing, basically when i pray i always get this 'image' of god and i keep thinking that i am commiting shirk when this image comes in my head, like i would be getting ready to prostrate and the image forms in my head and i immediatly think i am bowing down to that image, not allah himself. its really annoying does anyone else have the same problem?