Hitting a wrong ball

Question
I just finished a round and had the one of the most awkward situations happen pertaining to the rules of golf.  My tee shot was close to a tree, as I was wasn't able to see the outcome, I was playing a draw shot, I asked my 2 other playing partners to watch the shot, I took the shot and both said they didn't see it, so I played a provisional, again they said they didn't see it, so I played a second provisional which we saw.  while approaching  the green, I found which I thought was my original (callaway no.4) it was buried a bit but I didn't bother checking for my markings.  I hit this ball once and started walking towards the green.  At this point I found my provisionals and my original.  I stopped playing the wrong ball I hit and played my original with a a two stroke penalty, was this the correct thing to do? My original was also a callaway no.4  

Answer
Mike,

You did everything in accordance with the rules. Read below.

b. Stroke Play
If a competitor makes a stroke or strokes at a wrong ball,
he incurs a penalty of two strokes.
The competitor must correct his mistake by playing the correct ball or by proceeding under the Rules. If he fails to correct his mistake before making a stroke on the next teeing ground or, in the case of the last hole of the round, fails to declare his intention to correct his mistake before leaving the putting green,
he is disqualified.

Well done,

Michael