My Son Tells Me He Needs to Poop but Screams NO If I Mention the Potty

Having a bowel movement on the potty is one of the last things accomplished when potty training. Don't push him. Also, if he has any history of painful constipation it will delay bowel training because they associate bowel movements with pain. Focus first on peeing in the potty and the other will eventually come. Just a warning though, most boys are not interested in potty training till after age 3. I know that are some boys that are potty trained for the most part by age 3 but most are not. If he completely refuses to use the potty at all for peeing and is getting upset when you try to get him to, you would be better off backing off for a few months. Don't put the potty away though. Leave it out in plain sight but just don't talk about it. Give him some time to adjust the potty without it causing him any obligations. You might find him testing it out. If you do, don't interrupt or let him know that you noticed for a while. Give him some time to play with it, several weeks at least.

I think you need to stop talking about the potty. I know how frustrating that must be because for an adult, what he is doing makes no sense! But it makes sense to him! I am not a fan of "running around naked"...uh, gross!! When he says he has to poop, aplaud him for telling you! Ask him how he feels during and after. Hopefully, after he goes in his diaper he will ask you to change him. What worked for my son is I let him see it and smell it and we talked about how it was smelly and messy. Bring him into the bathroom when you go and give him treats just for sitting on the potty. Potato chips worked with my son. Sounds like your son is feeling very pressured so just lay off the rushing to the potty for a week or two and use pull-ups. Used correctly, they work great!

I would stop mentioning the potty at all right now. Put him back in diapers and stay there with no mention of the potty thing until the end of February.

I'm an advocate of child-centered potty training though. Just like you couldn't train your child to walk (because he had to be physically and mentally developed in order to master this skill) you can't train your son to go to the potty. You can train yourself, if you have a compliant child. But it doesn't sound like you do. It sounds like you have a son who wants to own mastering this skill. So, let him.
The "work" you do with him to get him ready is...
*start giving him multiple commands at one time "take these keys to the kitchen table and then go into the bedroom and bring mommy the brush".
*get him super comfortable with the gross motor skills of dressing and undressing quickly - especially his pants. So, he starts to get himself fully dressed in the morning and at night. work with him on buttons and zippers.
*praise him for things that he does well, but don't offer him a reward to do things that come naturally - just like walking you didn't give him an m&m.... instead as he gets himself dressed and can master the zipper and the button. Say something like "good job big boy. you did your pants so well". Let him know that the praise from you and the feeling he gets by knowing he did something well is the best reward.
*love that he's still a baby. Potty training makes him officially a big kid. hold onto his baby-ness for another month or so. Until HE'S ready.

Good Luck!

Get the book "Everybody poops." My daughter did the same thing, that book got her over whatever it was that had her scared.

We had a special book that we would only read to him while he was on the potty. (How to potty train your monster) He loved (and still loves even though he's almost 6) that book! We'd take him to the potty around the times that we had noticed "action", no expectations, have a seat on the edge of the tub and start reading.
It took some time, but it was a lot less dramatic that way.
Good luck! :)