no sex 😔 please help

So I'm currently 14weeks pregnant and my SO doesn't want to have sex with me at all. He is normally the one to initiate things but for the past several weeks he won't even touch me. I asked him last night what was going on because we have always had a very healthy sex life. He said " I've just had zero sex drive lately. " I asked him if it was because I'm pregnant, and his answer was no. He began to apologize and I asked what we could do to change it, but he says he doesn't know. So now  I'm stuck and over  thinking every tiny thing I just don't know what to do to get back to normal.