Firstly welcome to the forum but sorry under these circumstances.
congratulations on birth of your second child.
you will be busy looking after two children and coping with the changes birth and breastfeeding bring to your body and your emotions.
You wrote that you understood your husband was keen to have sex, did you discuss this ?
when you are not so upset would you be able to listen to him explain what happened and for him to listen how you feel.
I am sorry you feel this way, do you have someone to talk to.
please feel free to post here again as we are listening and you are not alone.