I suspect you have a problem here, @Awjaysus. You are married to a man with a tendency to control. You need to challenge every single expression of that.
What's this nonsense about your H's MH suffering if the place isn't kept to his standards?
To me that sounds like an ideal way of asserting that he is asserting that his standards are the ones you have to live up to, jeopardise your recovery from major abdominal surgery trying to keep him from having some sort of a wobble.
He needs to go to see a therapist if he has mental health issues, not make you run around like a scalded earwig trying to keep house to his requirements.
Tell him this is what he needs to do.
He is not your boss. You have to feel comfortable in your own home too. He is not the employer to whom you answer about how you spend your days. You are not his housekeeper. Don't let him get away with any more of the MH excuse for giving you a hard time. His MH is his responsibility alone. If a messy house makes him anxious now, just wait until your baby is a toddler.
There is absolutely no way you should be doing grocery shopping so soon after a CS. There is no way you should have to push a pram with bags of groceries and baby home from the shop.
Either your H does all of that and puts everything away when he gets home or you order everything.
I am appalled that he spent his day helping a friend while you had all of that to do, and when he got home he ripped into you. Leave him with the baby for a day, go to see your mum or just lock yourself in the bedroom to get a bit of relaxation with earplugs in, and see how he gets on with the feeding, the burping, the soothing to sleep, the nappy changing, the rinsing and repeating. Let him see how he manages with his 'to do' list.
And go back to the hospital you delivered in to get your headache problem sorted out!
Do this ASAP.