Yes... several times. But one in particular stands out. And (obviously) I wasn't looking for it when it happened.
I was at college, and a friend was trying to convince me to go to a Christian college conference. (I was a Christian already; it wasn't a matter of conversion here.) I pretended to listen, and was trying to figure out how I could tell her "no", because I didn't have ANY money for the trip, etc., and I didn't know how to turn her down with some other good excuse.
So, I said, "Well, you know, I just don't think ..." and right after I spoke those words, it was like something intruded into my mind from absolutely nowhere, "IT DOESN'T MATTER WHAT YOU THINK." It was like God simply entered my head and stamped these words, or thundered them, all over all my own words and thoughts; I'm not sure I could say I audibly heard it. But it was very clear.
I was so completely shocked, I just stopped in mid-sentence with my jaw dropping. My confused friend finally began to talk, changing the subject even. Eventually, I closed my mouth and reached over and took a registration form and filled it out. I've never experienced anything like that since.
I don't know if something like that experience is what you meant. ? (I don't stake my faith on it, btw.)
I'm confident that there ISN'T a requirement for something to "happen to" you, at least like you might imagine. That's like thinking that grass must snap up out of the ground, or else all its growth is invalid. If you have a wrong assumption, you can feel frustrated when the result doesn't come.
It seems to me that you God has gotten your attention, despite your thoughts to the contrary.
So, here is an interesting chapter on searching for God, by AW Tozer (I think he was a presbyterian minister). The subject is about our searching for God. (It has, unfortunately, several typos in it.)
http://www.worldinvisible.com/library/tozer/5f00.0888/5f00.0888.01.htm
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