If your spouse filed Married Joint, that means, by definition, all your income and deductions were supposed to be on that same return. That's what joint means, both of you on the same return. He would now have to amend his return to add all your information.
Amended returns are filed on paper by mail and it takes the IRS 6-12 weeks to process them.
It is entirely possible that money will be owed back out of the original refund because he got all the deductions for both of you and basically said you had no income. Adding your income may cause some of the refund he got to be returned.
You can not file separate now unless he amends his to separate also, in which case neither of you will be eligible to receive any child related credits. You cannot file joint without including him on your return, and you cannot file single because you're married. He had to enter your social security number on his return so now any return you file will be rejected,
Amend instructions:
https://ttlc.intuit.com/replies/5567856
