Quick answer
Is it dangerous to use a spell from the internet or TikTok?
A spell on TikTok looks harmless: a few words, a candle, a wish written on a bay leaf. What the video never shows is where the spell comes from. Every spell belongs to a system with its own rules, and using one means stepping into that system on its terms.
If you do not know the origin, you cannot know what those terms are. Most of the time nothing happens, and sometimes something answers. There have been people who used simple money or knowledge spells and ended up inviting entities into their lives for good.
The full argument is in why you should never cast a spell you found on the internet. If you already tried one and something has felt wrong since, read can a spell be reversed.
Questions
Are money spells safe?
Not when the source is unknown. Simple money and knowledge spells are among the ones that have left people with entities in their lives for good.
How can I tell where a spell comes from?
Without training, you usually cannot. That is exactly what makes following one a risk.