Thomas, as I was Baptist for 20 years, I do know what you are experiencing. Maybe it was a little easier for me because I think God lead me to it slowly and had been preparing me before I even attended my first service. It helped that I had almost two months of typica (Reader's) services before I had my first liturgy because that gave me a couple of months to get used to the icons, candles, the prayers, etc. before my first liturgy. By the time I had my first liturgy, I was hooked. When I had no clue as to what was going on, it made me want to learn. If I had faced that my first time out, it might have very well scared me off. When you don't come from a liturgical church, that first liturgy can be rather scary!
May I recommend a book that might really help you? It is a book called "Thirsting for God in a Land of Shallow Wells", by Matthew Gallatin. He had been both a fundamentalist and a charismatic before he converted (in fact he was a pastor of a charismatic church for several years) before converting to Orthodoxy. He discusses many of the topics that those of us who come from an evangelical or charismatic background, and I think he does a very good job of it. It is published by Conciliar Press (www.conciliarpress.com
) and costs about $15.00 (give or take a buck or two).
He discusses Sola Scriptura v. Scripture and Tradition, the Theotokos, venerations of the saints, infant baptism, the sacraments (especially the Eucharist), using prayer books as opposed to strictly spontaneous prayer, and many other topics. After I read it, I gave it to a friend of mine that is Baptist like I was, and she loved it too.
I know that before I started attending the Orthodox mission that scriptures were leaping out at me that I saw the Baptists not incorporating. The two biggies for me were how Baptists see Communion. The verses that I was reading made it very clear to me that it *is* the Body and Blood of Christ. Of course, the Baptists (and many of the evangelical and charismatic churches deny that it is His Body and Blood). Also, the verses about confessing our sins to one another and the apostles being given power to absolve or remit sins (how could they do that without hearing them first).
Be patient with yourself. Don't do things unless you are comfortable with doing them. I have found that priests are extremely patient. Stand as much as you feel comfortable doing. You do get used to it after awhile. There are certain parts of the service that you should definitely stand for: the Gospel reading, the reciting of the Creed, the Eucharistic prayer, and during Holy Communion. Other times, feel free to sit if you are tired.