Check/revise your passwords and use 2 factor authentication where ever possible.
Look into credit monitoring companies e.g. Life Lock. There are even some free credit monitoring companies that can/may help e.g. Creditwise at Capital One
Have a fraud alert placed on your credit bureau credit report. It is different than freezing your credit.
Medical care can be charged through identity theft.
Since it is tax time, work with IRS to make sure someone else does not file an false income tax return and get a refund.
Edited to add: Work with your bank and any other places you have money e.g. brokerage house(s) to see if anything needs to be done.
Now that your credit card is locked, determine what companies have automatic payments charged to it. You will need to make changes there to a new credit card number once you get one. Maybe notify all those companies of what is occurring so it will not impact your credit score.
Make a list of everywhere you have saved your credit card number to make purchases faster and easier e.g. Amazon, where you get your prescriptions filled, Costco, Walmart, ---> you the gist of it. These will needed to changed (or not). Consider if you want to keep credit card numbers saved at retailers. IMHO, not a good idea because if you have a data breach of your credit card, you will have to change all of them and that is a lot of work including just figuring out where they are saved.
Lots of luck....
