Yes, that is one of the difficulties of implementing the Affordable Care Act (ACA, or 'Obamacare').
You are asked at the beginning of the year to estimate your income for the year, which is what your Premium Tax Credit (PTC) is based on.
However, if by the end of the year, your income situation has significantly changed (increased), then you may be forced to repay some or all of the PTC when you file your tax return.
To prevent this in the future, make sure to contact the federal or state marketplace (wherever you go the insurance) immediately if there are any changes to your filing status, number of dependents, job status, or other income - so that the marketplace can adjust the amount of PTC that you are receiving.
