I once read that the reason it is called “An Act of Contrition” instead of “The Act . . .” is because there are so many possible ones. I also read that it may actually be better to make your own, since it will generally come from the heart instead of just being a memorized “prayer” that is said by rote. I don’t know how true these statements are (and I read them some 20 - 25 years ago).
My problem with the Act of Contrition is that I generally pray in English, but after confession, I am expected to make an Act of Contrition in Spanish. It is not written on a card in the confessional (in fact, we don’t really have any confessionals - I’ll explain later), so I can’t make use of that. Translating on the fly (as they say) isn’t that easy, so I generally make one up for the occassion.
As for the lack of confessionals. In my chapel (and in most other chapels in the parish), confession is held in the Sacristry before Mass. In the parish church, it is held outside, away from the people that are arriving. Or, if you go to confession during the week, (yes, we have confessions every day) it is generally in the priest’s office. So there are generally no confessionals here.