I play the violin. I have for about 15 years now and play for a couple of area orchestras and weddings and such. Every once in a while, I'll mention to someone that I am a violinist as part of a conversation. As soon as it leaves my mouth, I cringe, knowing what is to come next. "Now, do you play violin? or do you play fiddle?" or something to that effect. Of course, the dreaded comment is accompanied with a huge, satisfied grin.
Let me just settle it once and for all. There's no difference in the instrument itself. You could say that a real fiddle needs to be old looking and dusty and a violin is clean and shiny. But really... same instrument.
So really, it's style. It's not unlike the difference between baroque violin music and romantic violin music. It's a style, a genre even.
I grew up taking "classical" voilin lessons, and playing in orchestras and string ensembles. I can play my share of "fiddle" music and have even had a gig or two playing in an impromptu bluegrass band.
Therefore, the answer to your question is yes. I do play violin or fiddle. Now, stop asking. But if you must ask, don't think you're clever or original for doing so.