Hello A. S:
I read your request and felt a lot of confusion about potty training and re action of your son. It sounds like it has taken a turn towards the hardest training to do for you and your son. Pardon me if am wrong.
All this is happening because you have a lot to do in a day. You yourself, just had the baby, taking care of the new baby and the potty training at the same time. Your body is still recovering with the child birth.
Your son wants to be potty trained now, and he is not able to do so because of some drawback of the whole system in his mind that he is showing again and again when he goes in the diaper, and wants you to change him again and again.
To overcome this situation, you have to calm your nerves, be relaxed and feel that you have to find a way to help your son by overcoming this problem for him. Your mental readiness in a strong way to get the mission accomplished has to be there. You might feel it is there even now, but physically, mentally or unconsciously it is not working strongly to overcome this situation. Being a mother is the strongest power on earth that human race is surviving.
After giving yourself all the power to accomplish the mission, talk to your son in a calm loving and over protective manner about potty training. If you like let him observe his dad going potty. ( This fact is supported by expert child psychologists, and have proven helpful)
Let you child experience observing some other boys, if possible.
Let him watch a potty training video to feel that this is normal and everyone has to do it in a methodical way. Stress the importance of cleanliness also at that time.
After watching the video, seeing dad going potty or observing some other boys doing the same, whatever is possible, now talk to him about going to potty.
Try to make a set time everyday for # 2 training
Write down or just verbally find a method that suits you the best step by step. For example, five to ten minutes after breakfast every morning, when baby is sleeping and you can give him undivided attention and you are calm everything is in control, take him to potty. Make sure everything is comfortable around him. It is easy for him to sit on the potty. If he is not use the baby potty or potty seat. If he needs a stool to get up to the potty or wants to put his feet on the stool while on the potty give him that. Let him sit on the potty and be there for him.
Give him 10 minutes to go if he does not go. In case he does not go that is fine. In a very plain and calm voice tell him after ten minutes if you did not go potty you have to go in the diaper and I will change the diaper only one time. You will not ask me to change it again.
Use a firm and final voice. If you feel tell him not to throw a temper tentrum, as I want you to be happy and play or watch TV ( whatever the corse of action you have for him)
During the day let him watch the potty video, or talk to him before nap time again about the results and ask him to potty in the toilet the next day. Tell him good things about him and the fact that your son is good and he wants to do ever thing himself like good children and good people.
Ask him what he wants to do next after potty training and excite him about doing a special party or whatever he likes the most. Make him feel he is a doer. he can do anything that he wants to do as this makes him smart.
And eventually, a week of hard work or so will calm down this potty training activity once he starts doing it.
Your job is not finished here, you will have to keep the same practice for a while, may be months when he starts going by himself.
Also, make sure he is eating some veges and fruits, so he is not constipated and goes easily and his wait on the potty reduces naturally.
While giving him examples for potty training, make sure your son sees only male, potty training, because every little thing distracts the child. Seeing difference in
the body of a male and female will also confuse him. We do not need any confusion at this point in his mind. We need him to be relaxed and at ease to understand and adopt going potty. I have used all this in potty training for children and is an authentic method from the advanced experts.
I hope this works for you.