Is this correct? Is it not "those girls are not interested in me?" Or do i just have low self-esteem?
No, that is the opposite! The sentence in this exercise means that I am not interested in those girls, not that those girls are not interested in me.
Doesn't nezajímají mean they are not interested? Shouldn't it be nezajímaji or nezajímám?
I can only see two questions other than mine and honestly they weren't helpful. But thanks anyways
Well, el_martillo asked almost the same thing. My answer to him should be an answer to you. "mne nezajímají" means that I am not interested. "já nezajímám" would mean that they are not interested in me.