I have worked with both light and evil magic as a long-time practicing Witch.
You might never be aware if someone has cursed you.
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Believe me. Others don’t find out until you tell them.
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However, if someone crosses you, puts a hex on you, or curses you, it’s usually a result of evil witchcraft, VooDoo, or a related practice.
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There are indicators, although they are typically small or almost unnoticeable.
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You might notice your cream or milk curdling while it should still be good.
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You might also notice a strange or slight smell of sulfur or a burnt smell.
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You may be plagued with bad or frightening dreams or sleep paralysis.
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You can become sick, weak, or unable to eat.
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You may become lethargic or easily irritated.
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The first thing you should do if you believe a spell has been cast is to sage your entire house.
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In addition to that, consulting a priest, witch, or spiritualist may be necessary.