Miracle or Logical Explanation?

Why is it that we find it so much easier to search for the logical explanation in a situation, rather than recognize and accept that maybe God really did hear and answer our prayers?

Exhibit A: Back in August we had a little problem with the Saturn. Actually, a big problem with the transmission to be specific. Two different mechanics told us the transmission was messed up and would cost us many many dollars to fix. So as we were wondering what to do and where we would come up with the money to do it, we prayed that God would help us out. A few days later we took the car in to Mechanic #3, who examined the car and told us there was absolutely no problem whatsoever with the transmission. And the car has run perfectly fine ever since.

Logical explanation (there never was a transmission problem and the electrical system reset automatically), or miracle (God answered our prayer by fixing our car) ????

Exhibit B: For the past few weeks I have been getting a lot more headaches/migraines, been very sensitive to light, and noticed a general blurriness. On Friday I went to the optometrist, thinking I just needed a new contact prescription. The optometrist said she could not correct my vision fully, even with a new prescription, because my optic nerves were swollen. My pupils were also not reacting correctly to light. So I took my referral to see a neuro-opthalmologist ASAP home with me, and promptly googled "swelling of the optic nerve." For the rest of the weekend we worried about horrible things like brain tumors, MS, intracranial pressure, and permanent vision loss. I also had terrible headaches most of the weekend. So today we went to my appointment where I was pronounced 100% healthy. Perfect vision, perfectly responsive pupils, and absolutely no swelling of the optic nerve. Also my first headache-free day in a while.

Logical explanation (there never was anything wrong with my optic nerve and the optometrist just read it wrong), or miracle (God heard the many prayers going up this weekend and healed whatever was wrong with my eyes) ????

Why is it harder to believe in the miracle? Why do we pray for God to work in our lives and then search for a way to explain it ourselves?

I want to be a person who believes in miracles...