This is a rather stupid and super-vague puzzle that I made, so it's no wonder that no-one figured it out. Then again, this
WAS my first question on this site, so I was pretty inexperienced with making proper puzzles back then.
Anyhoo, here's my official answer to my own question.
(The Stupid) Solution:
Banana
The Explanation:
Curved like a circle
Bananas have a curved shape, like, or similar to, a circle.
Knotty Sides
Bananas have that one elongated and knotty end on them.
My color is . _.. . (old women brains)
This is a conveluted part. ". _.. ." is Morse for "EDE." If we translate that to their numerical position in the alphabet, and we get "575." Now for the other part, we have some puns: old women=nanny+ brains=motor-nannymotor. This sounds like nanometers. Combinee with be 575, we get 575 nanometers, the wavelength for the color yellow. Like I said, this is pretty dumb. It's even more so without any given context (which was not given.) And bananas are yellow.
Specks of evil on my enlightened self.
Most bananas, which are yellow(~white=good/enlightened), have a few black(=evil) specks on them.
A strong mask to hide my true self. To protect the weak of what I am.
Bananas have peels to protect their fleshy insides.
A pretty stupid puzzle for sure. Now that mystery is cleared up!