I'm all for rough and animal play but not when it comes to anal sex.
Your partner needs to know that there are real concerns about anal fissures and tearing. If you're doing a lot of bleeding, and you're not using lube?
I'm just shaking my head. You're a sex worker?
Your body is your frigging TEMPLE! Look. Enjoy the guy. I'm already not liking him because it's sounding like he's actually hurting you and either not caring or oblivious.
You're asking for opinions and you're getting one from an older woman who worries when reading stuff like this.
Take care of you. Step back. Decide how you're going to go forward the next time you're having sex with this guy and the possibility of anal comes up.
The others have offered some good advice. I would suggest going REALLY slow. Telling him to stop when he first puts the head of his cock in your bottom. Let your sphincter muscle get used to his love muscle.
YOU control the penetration. Not him, at least not until you're more used to it.
And the tearing and not being able to poop properly afterwards? Don't do that to yourself. Well, not again.
Your bottom isn't like your pussy. It doesn't stretch and then go back in the same way. Not trying to be gross but wanting to help.
Be smart. Then, have a blast with this guy, and write again and tell us EVERYTHING.
I just think that there are a lot of places to go, and explore, without physically doing yourself harsh, potentially permanent, harm. (My old adage is a little hurting is good. Harming someone is bad. Syntax. I know.)
Good luck.
Best,
Elisabeth