Get your taxes done using TurboTax

I just finished filing my wife's and I W-2s, 1098s, and other documents. I just found out that i had a 1099-SA form i forgot to file. My federal and state return was accepted and now i am awaiting payment. Does this form make a difference whether or not i file it? and if so, how hard is it to file an amended return on TurboTax online? when can i do this?