I’m proud of myself for not being fake. I’m difficult sometimes and have a few screws loose, but I am 100% me.
Be mentally unstable or eccentric, as in Anyone who approves that purchase must have a screw loose. This term likens a mental weakness to a machine in which a part is not securely fastened. An antonym is having one’s head screwed on the right; for example, She’s very capable; she has her head screwed on right. [Slang; early 1800s]