Amending State Return ONLY?

Hi folks,

 

I neglected to claim about $1200 in deductions on my state return which are not claimable on my federal return (contributions to an Oregon Individual Development Account).

 

Is there a way to ONLY amend my state return via TurboTax online, or do I have to amend both? When I click "amend" it takes me to federal and THEN state. If not, will this cause any issues with my federal return? I have already filed both my federal and state returns and received my federal refund, so the less messing around with this stuff I end up doing, the better.

 

Thanks!