In normal times, you would expect to hear from the IRS 12 weeks after an amendment. This year, the IRS is very behind and it may be many months before they get to the amendment.
If your unemployment was less than $10,200 and you did not claim it, then probably no change to your taxes by claiming it. If you collected more than $10,200 the amount over $10,200 would result in you owing more taxes.
All of your income including any unemployment was supposed to be entered on your tax return, so it was correct to amend your return after it had been fully processed so that you could include the unemployment. The tax law excludes the first $10,200 of your unemployment from federal tax if your AGI is $150K or less so you might not owe any extra tax, and could possibly get a refund of tax withheld from the unemployment. You will have a long wait for the amended return to be processed.
Even during “normal” times it takes about four months for the IRS to process an amended return. During the pandemic and due to the severe backlog at the IRS it is taking much longer—six months or more for many amended returns. Do not expect quick results from amending. When the IRS issues a refund for an amended return it will be by check. They do not make direct deposits for refunds for amended returns. You can watch for information here: