The New York Times’ article titled “Overcoming a Lifetime of Stage Fright” in its Sunday Review page describes how a female pianist who has suffered stage fright in her lifetime felt when she played piano in public at an international airport: It goes:

> 
> It had been 40 years since my last recital, but the first time I
>  played the piano at Mineta San Jose International Airport, my body
>  responded right on cue. My hands turned wet with sweat, my heart
>  pounded, my feet gave a soft little drum roll on the floor. 
> 
> 
> I was there because, at age 59, **I was determined to** overcome a
>  lifetime of stage fright. I had quit playing the piano when I was 19
>  because of my anxiety.
>  <http://www.nytimes.com/2015/05/31/opinion/sunday/overcoming-a-lifetime-of-stage-fright>.
> 
> 
> 

OED defines “determine” as a verb meaning (2) firmly decide, as well as “determined” as an adjective meaning “having firmness of purpose, resolute.”

Are the meanings of “I was determined to do sth” and “I determined to do sth” same and interchangeable? If No, what’s the difference of meanings / nuances between them?