Joanna, thanks for your eloquent and very accurate explanation of personal prayer in tongues. I too experience what you have described. It can be very powerful. God is so awesome to allow us yet another way to praise Him!
In my Charismatic community, we do pray as you have described in groups, for short periods of time as the Spirit moves us, during our prayer meetings. No interpretation is needed for that because the tongues are NOT directed at the whole community as a prophetic word in tongues would be. It sounds to an outsider (which I used to be) like tuneful humming, quite pretty actually, but not intelligible. It’s not intended to be intelligible, it’s between the prayer and God Himself.
When such a word is spoken in tongues to the whole community, an interpretation has ALWAYS followed, in my admittedly limited experience. This gift is rare, probably the least used of all the Charismatic gifts with our community.Our Community has a particular calling to praise, especially in music, and to teaching gifts. Each community is different. And like all human endeavors, even those with God at the helm, we have some weirdos in our community.
We try hard to love them as Jesus would have us do!
I’d urge all readers to recognize that this is a valid and approved lay apostolate, and that we recognize completely that the charismatic way is NOT for all Catholics, nor do we try to convert people to it.
Just because it may not be for you does not mean it’s wrong. The Cistercian third order lay movement, for a random example, is not for me personally but I certainly recognize their powerful gifts and presence in our Church and rejoice that they exist at all.