just turn the key, little missy

So this morning I went for a run at my favorite park closest to me. When I got in the car and tried to start it, I couldn't. I mean the key wouldn't turn in the ignition. That happens to me frequently so I commenced jiggling it, then trying to turn the wheel really hard in case it was locked but all produced no results, other than very sore fingers. After at least 20 minutes of this I gave in and called my friend N. She came over with a can of WD40 and I sprayed the heck out of the lock. Still no luck. We went back to my house to get my extra key. Still no luck. A fellow parked next to us asked if I'd tried X, Y and Z. Of course I had. Still, he had to give it a shot (now, this is exactly how I act in these situations so I couldn't really fault him for having to try it himself). Low and behold, he was able to get it started. Then of course I felt pretty stupid, but I think it was either the WD40 having a chance to work or the fact that the dude was way stronger than me or both. Anyway, I have been able to start it myself twice since then but I'll be living in fear until I can get it fixed.