its waswas...it happens to me too sometimes,after i have commited sins or when my iman is very high,during these times it happens to me too.The more you think of it the more it would bother you,and it would be normal then,when you pray you will remember that you have this image when you pray and that will be the norm and you will always remember it. So the best thing to do is to try to forget it,if it happens stay calm and dont think of it,instead move it to the side,turn it upside down,or do whatever else with your mind to humiliate that figure.
So what i do is if it happens i move it to the side,so i am not making sujood to it,i turn it upside down,i cut his head,i put a sword in its neck,i slap him or smth like that,whatever it is that i think of that second.Or move it to the side and cut his legs,so he wont move before you again.Shaytan i using your imagination to affect you,you can use your imagination too to stop it.
Make duaa,and dont let it affect you much,thats what the shaytan wants,and Allah knows your true intentions.May Allah help you.
