How Long a Spell Lasts

This is a turquoise bead. I used several of these beads along with chips of Tiger eye and amethyst in a protection spell for my truck. According to legend, turquoise will turn green to warn of danger. The beads were a different weren't this shade of green when I made my pouch. They were all light blue.

How long ago did I do the spell?  I can't remember. I know it's been a while. I know I've renewed it a few times, though I didn't open the pouch. So the question is if I am in danger now or if I was in danger in the past but my spell saved me.

I've decided the beads and stones have served me well and I intend to return them to the Earth. I'm going to do some maintenance on the truck (including cleansing to remove any negativity), and then I'll probably do an uncrossing ritual since I don't know where trouble could come from. The pouch has spent the last two weeks in my desk drawer because my inlaws borrowed the truck so I took out my weapons and my magick. Did the beads turn green while in the desk drawer? I have no way to know. I'm assuming that since this was a car protection spell the danger stems some something highway related, but what if this is not the case? When I did the spell I said that the truck, myself, and any passengers be safe from harm. I was thinking about it as when I was in the truck but that's not how I worded it. Now you see why I'm not sure if I'm in trouble or not.

I'm going to make an entirely different mojo bag for the truck. And I think I should make more effort to tend to it. Maybe it should be renewed as often as the oil is changed.