First time anal.

My biyfriend and i want to try anal. But im scared of 3 things.
​Pain, embarrassment, and poop!
​I scared of getting poop on his member.  I mean, i clean myself up well but its just always been a fear of mine. 
​Some girls says it hurts, some say it burns and ither say it doesnt hurt at all. 
​Any advice? How do i avoid embarrassment, pain and getting poop on him (if its even possible).