It's very common in abusive relationships for the victim to kick off because of the cycle of abuse. 'Walking on eggshells' is tension and you know that there will be violence, so, unable to stand the tension you kick off and the inevitable happens. A 'honeymoon' period may happen which is what you are trying to get to and then the tension starts up again.
Your partner knows you will kick off if he calls you names so he uses that as an excuse so he can beat the crap out of you. This will escalate and I believe he was very into you having a child because abusers have more control when you have children.
You should not be having counselling with an abusive partner. You have a child and your first priority is your child. Your child needs to be out of this very damaging atmosphere. I can't imagine how terrified he is of all the arguing and violence.
I understand from what you've posted and the fact that you were in counselling with this person a few months ago, that you want to remain together but unfortunately that can't happen because of the effect it will have on your child. If you want to remain in a relationship with him, then, in order to protect your child, please find someone else he can stay with such as a close relative. In that way he isn't further damaged by the abuse he is witnessing.
Physical abuse doesn't just happen in a relationship, it's a gradual process and there will be other forms of abuse such as coercive control, financial abuse, snide comments etc etc and your young child is absorbing all this. He will also be stepping on eggshells in order not to 'set daddy off'. He is learning how to speak to and treat women and how to behave in a relationship by observing you and your partner's relationship.
No one wants that for their child.
Please contact the CABx or Women's Aid in order to get advice on how to move forward. Get some counselling in order to get some support during this difficult time.
This relationship is not going to get better. This man is not going to change. This is it. His behaviour is escalating and you are at a lot of risk so please get a safety plan together with the help of a DV org.