When you want to add your own font besides the ones that normal system fonts, you have to bullet proof your fonts with @font-face. You are on the correct path the way you have started to do it. But you also have to include different font types of your font for various browser integration like ie, chrome, safari, FF etc. The different font types include woff, ttf, eot, svg etc.
You can refer this link , a fantastic article by Paul Irish. This explains what goes on in defining a font type for your webpage.
Now another reason you could run into trouble in loading the font is when the font file itself is not loaded properly. Thi happens when the source url provided for the font file is not correct.
In your case src: url(optima-regular-webfont.woff);
line of code instructs the server to look for the font file in the same lever as where the page file ( html) is loaded from. Check if that is the case for you.
Hope this helps.
EDIT:::
In one of your comments you had given the link where the site is hosted. The console gives me this error..
Failed to load resource: the server responded with a status of 404 (Not Found) http://sarahmyra.com/beta2/css/optima-regular-webfont.woff
Failed to load resource: the server responded with a status of 404 (Not Found) http://sarahmyra.com/beta2/css/Optima_Medium.ttf
Now please check the path to font file.