I forgot to put my medical tax credit on my tax forms. How do I amend my state and federal taxes now?

there is no federal medical expense credit. for medical expenses to be of benefit for federal purposes they first would have to exceed 7.5% of your adjusted gross income. then the deductible amount of medical expenses + the deductible amounts of other schedule A expenses would have to exceed your standard deduction. finally, you would need to have a tax liability before the deduction of either the itemized or standard deduction.

don't know what state. not all states allow itemized deductions.

to amend open your return to amend and add the medical expenses for schedule A.