Is...is this supposed to happen!?

[Black Boo]

So I'm playing through Twilight Princess off of memory, and I was heading up to Goron Mines when I realize I have no Hylian Shield! So I go running back down the mountain and around the fields to get money. So I go to Kakariko and mosey around, look around, and there's one thing I want to tell you. I go in at night and look at the watchtower. Nothing's there. So I keep going around the village and killing the crows. Then I head to Kakariko Graveyard to move some headstones and try find money, and beat the flock of crows to get a bunch of money.

I go in, move the first headstone on the right. Ten rupees. Awesome. Then I walk on over to the headstone on the left and move it. Guess what comes out. A POE!? Now hang on a sec, I thought that they're only supposed to appear after you find the one in Jovani's house! So I book it out of there as I was getting beaten to a pulp, fighting a foe I couldn't see.

So I go out and I'm like "That's odd...they're not supposed to show up yet..." So I think it was just a glitch and walk back in. Now there's TWO! Apparently there's one there right off the bat, but he wasn't there when I went in the first time! So I run past them and fight the crows, get my money, then get the hell out of there! Then before I leave, I look up at the watchtower again. Guess what, THERE'S A LANTERN.

Did my game like severely mess up or can this actually happen?

PS: I got my shield.