Oh op l am so so sorry, this is never acceptable whatever you said to him, never.
Being drunk is not an excuse,
Being angry is not an excuse, he could choose to walk away
He has shown you what type of man he is
He will not change.
Please make plans to quietly leave, this cannot be your future or your sons.
Please call womans aid, tell your friends and family today.
Leave first with all documentation, birth cert, bank statement, mortgage or rent tenancy agreement, and special things he may destroy, baby items .
Tell him after.
He could have killed you, what would happen to your baby if he does next time, please don't take that chance, you have your whole life ahead of you...
When he says he is sorry, he loves you, and will change remember this,
Love is kind, love doesn't hurt, good men never hit, not when drunk, angry, stressed, or depressed, decent men don't hit ever.
Abusive men don't change.