Ok so firstly whatever you decide to do is up to you, it’s a valid decision and you don’t need to feel guilty or ashamed of any decision you make.
everything I say now is just the things I would consider before making my decision if I were in your shoes.
have a think about what you’re scared of, and if logistically any of that can be helped. For example, can you get extra help, can your DH step up more? It sounds like he’s not overwhelmed right now, so presumably isn’t doing 50/50 since you are completely overwhelmed - make sure he starts doing more before your due date if you decide to go ahead, but also in general if you decide not to.
are there any other things you can afford to outsource - childcare, cleaning, meal kits to reduce shopping and cooking time etc.
can DH take some leave which would allow you to go back to work quicker if that’s what you wanted, or could any of your job be adapted so you can work from home or PT for example
think about what is temporary Vs long term. Will you still be overwhelmed in 5 years? Will this period of being overwhelmed be ok if you know you’ll make it through in x years
and once you’re not overwhelmed would you regret making the decision to end the pregnancy now (and if the answer is no that’s ok too!)
then if you are leaning towards continuing you may feel better to think about a logical plan and how you will cope which may confirm your decision either way
or if you are leaning towards ending the pregnancy do a little more research on that and what it involves so you can make an informed decision.
i also think your husband needs to be more supportive. It’s all very well for him to think this is a miracle - and I understand his point - but clearly he isn’t doing 50% of the parenting, he isn’t being pregnant or dealing with sickness and general pregnancy and labour, hormones etc. he isn’t telling his work he’ll be taking a 3rd leave. If he can’t understand how the news affects you differently then he’s being very selfish.
good luck op.