In the form of "creerse" it can also mean "believe in yourself" which used to have the same connotation of being mistakenly overconfident, although in the last couple of years I've started to see more "debes de creértela" Linkedin memes which have the opposite (true belief) connotation, more like "fake it till you make it".
If anyone's confused, don't worry. This verb always means "believe", the only difference is in the subtle connotations but they never affect the actual meaning.
I found an article that offers "fall for it" as a translation for "creérsela" (te la creíste/se la creyó) and I agree.
https://www.tellmeinspanish.com/grammar/creer-vs-creerse/
In the form of "creerse" it can also mean "believe in yourself" which used to have the same connotation of being mistakenly overconfident, although in the last couple of years I've started to see more "debes de creértela" Linkedin memes which have the opposite (true belief) connotation, more like "fake it till you make it".
If anyone's confused, don't worry. This verb always means "believe", the only difference is in the subtle connotations but they never affect the actual meaning.