An Unusual Mix-Up at University

Salam alaikum, I need some advice. I’m a Christian studying at uni in Australia, and something weird happened recently. I accidentally said the Shahada, and now I’m confused about where I stand. It started when I passed a stall offering free Qurans. The brother there handed me some pamphlets, and I took them just to be polite, but later threw them away because my parents would freak out if they found them. After that, he kept stopping me for chats each week-sometimes up to 30 minutes. I’m too shy to cut things short, so I just went along with it, which is partly my fault. Then one day, he asked if I was ready for the “first step.” I assumed it was about submitting to Allah, which as a Christian I already believe in, since we worship the same God. I was really tired, zoning out with music in one ear, so I didn’t pay full attention. He told me to repeat some Arabic words, and I did, but when I heard “Muhammad,” I got a bit worried. Only later did I realize I had just recited the Shahada. He then congratulated me on becoming Muslim, and I was so shocked. I have nothing against Muslims, but I come from a Christian family and never intended to revert. If I had known what I was saying, I wouldn’t have said it with that intention. I don’t blame the brother-it was my own mistake for not being more aware. My question is: what do I do now? Am I considered a Muslim even without meaning it, or do I remain Christian since there was no real intention? I really don’t want to disrespect Islam, so any advice would help. JazakAllah khair. Sorry if this sounds silly, but I genuinely need guidance.