Last Wednesday you said you were meeting with a WA worker - have you met her yet? Do you have a contact number for her? If so, give her a call as the national helpline is often oversubscribed, especially at weekends, and it may take some time before someone gets back to.
As for it being 'your word against his', it's improbable that SS were alerted to concerns about what is happening to you and to your dc because you are abusing him and I have no doubt your account will be believed.
With regard to him 'being lovely' for the past 3 weeks, he knows that if you tell anyone what he's been doing to you and the dc, his game is up and he'll lose out on having you to wipe his self-entitled abusive arse and having you be his personal punchbag when he feels like relieving his non-existent 'stress'.
Being 'lovely' is simply another way in which he fucks with your head and leads you to believe there must be something wrong with you rather than the truth, which is that he's a thoroughly nasty screwed up piece of gobshite who's not fit to be a husband or a father.
When abusive twunts fear their victims may get away from them, they can easily do 3 weeks and more of 'good behaviour' standing on their on their minisicule dicks.
After he's done 3 years of never putting a foot, or a fist, wrong there may be some faint hope he won't relapse but, as the saying goes, leopards don't change their spots and there'll always be a chance he'll revert to type.