No, Laura, nothing is wrong with you apart from what is wrong with all of us in our fallen state. To tell you the truth, your post makes me respect you--the fact that you want something REAL, and aren't falling to a fake, self-fabricated delusion of a so-called tongue brings hope to my mind that SOME are hungry for the true Spirit, and not a false form of godliness.
First of all, what is this about murmuring? Has someone told you that God cannot Speak for himself? Did they say that you have to HELP HIM speak? Those who truly speak in tongues have no need to give the Spirit utterance. He gives them utterance. You don't have to start speaking in tongues of yourself for God to move. That is counterfieting his gifts--not recieving them. Do not be decieved. If you're going to a place where the pastor says "Now, do you hear that little voice in the back of your head? Just say what that little voice says." I suggest you pack up and LEAVE that church immediately, without looking back. That is not biblical, and it's dangerous. The same thing goes for anyone who tries to "teach" you HOW to speak in tongues, or who tells you to *rehearse* your prayer language. We are not to fabricate some copy of God's movements--God will move how he will move, and to copy and imitate such things is near to blasphemy, although God winks at ignorance for a time.
How DO we seek the Spirit, then? We certainly do not do so by wiggling about and thinking "well, if I shake this way long enough, maybe God will be in it after a while...if I mumble like this for an hour or so, maybe God will start to mumble for me." This is the road to deception--it's a lie of Satan, to keep us from the TRUE Spirit of God AND to keep us under SATAN'S control.
Rather, we seek the Spirit of God by praying continually, and running to him at the moment we make a mistake. Do not be discouraged--not everyone in the book of Acts recieved the Spirit the same day they believed. In fact, most of them didn't. Fall on your face continually. Pray continually. Welcome him. Sing to him. You don't have to murmur or do something weird to praise God. You don't have to counterfiet the movements of the Spirit to seek the Spirit. Just praise God. Talk to him. Pray concerning everything. Don't try to push God--that gets you nowhere. Rather, release everything. In my own experience, the baptism came when I stopped caring about things. The Holy Spirit will come when he will come. As for anyone who is impatient with you about this, I personally question whether or not THEY have recieved the Spirit.
I wonder about these who say that salvation is easy, or that Christianity is the "easiest religion in the world." (Well, for some forms of Christianity, they're right) Salvation IS NOT easy. It costs us EVERYTHING, although when we do give everything up, we find that we haven't lost anything. The road to Salvation is THIN. FEW find it. To save us by the skin of our teeth, Christ had to die. Now, when the Holy Spirit does enter us, or at least in my case, my thoughts were "Wow! I could've recieved him a LONG time ago!" but the road is not easy by any means--and it is full of tripping stones. I don't care if the man is reaching into people's ears and pulling out tumors, if he says that salvation is easy, I question him.
As for seeking God, I know what you're saying. "Yeah, yeah--I've tried that already." Don't think that there is something wrong with you, just because you don't immediately recieve the Spirit. I don't know if it's a good thing to break this to you before you recieve the Spirit, but MOST of those who claim to speak in tongues are faking it. Don't worry. Seek God and he will come when you are ready. Crucify the flesh daily. Sing aloud to him--praise him aloud when you can--in the car, in your bedroom. (Before, I've had to take a break and leave work because I had to shout.) Since you are a timid person (as I was when I was seeking the Spirit myself), this is something God can see as obeying and seeking him. I personally think that it's not such a big deal for louder people to do this, before they recieve the Spirit--because it's what they do already. Louder people often recieve God when they are softer than usual. RELEASE EVERYTHING, and praise his name. Remember: you can
think that you have left everything, but there are still things remaining. When he comes, you will know what I'm speaking of. Go before the church and have others pray for you, as well, and don't worry about the fakers. Just seek God.
I try to help
Blessings