Well, I'm glad to hear that you don't believe the universe was an accident. Neither do I. I'm undecided as to what I believe about various other "supernatural beliefs," but I do feel that God could conceivably begotten a Son without having had sex with His mother. I also believe that the Son of God could conceivably have done things we would consider impossible given our limited knowledge. I actually haven't believed in flying reindeer since I was a small child, though. As to the question you posed in your OP, I my convictions are only in those things that God has confirmed to my heart are true (the most significant of these being that He exists). I simply don't worry about the ones that He hasn't.
This reminds me of something that happened to me many years ago. Mormon children are baptized at the age of eight. Before this event takes place, the child is interviewed by his bishop (the local congregational leader) to ascertain that he understands the purpose of baptism and wants to receive it. I was waiting with my son outside the bishop's office for him to be interviewed when my son (just barely eight) turned to me and said, kind of hesitantly, "Mom, I'm not sure I should be baptized." "Why is that, honey?" I asked. "Well," he said, "you know that story about Jonah living inside of a whale for three days?" "Yes," I answered."Well, I'm not sure I believe it," he confessed. I laughed and told him that was okay, and congratulated myself on having a son who had learned that he didn't need to believe everything anybody ever told him in a religious setting. (My son, now 38, eventually stopped believing most everything else he was taught as a child, even though he still does believe in God. I'm fine with that.)