the left side of the camshaft popped up from the distributor

I was getting oil in one of my plug wires, so I replaced the o-rings. While turning the motor over, the left side of the camshaft popped up from the distributor. I had to realign the notches again, and may have turned it upside down. Now the camshaft won't drop all the way down on that side, and I can't lift it up high enough to spin it around. Does it matter which notch is on the top?