Could Kana really tell Shinichi's Migi apart from the other Parasytes, or was she just delusional? In episode 12, Kana tells Shinichi that she can tell Migi's emissions apart from the other Parasytes. However, she is shown as being on "cloud nine" for Shinichi - going as far as wrapping his hair around her finger like an engagement ring, and 


   near the end of the episode, she mistakes another Parasyte for Shinichi in the ruined building, leading to her death.


Since Migi states that her powers are increasing, it could be possible that she would be able to tell the Parasytes apart in the future. However, her death cut that development short.

Was she really able to tell Shinichi apart from the other Parasytes, or was she just delusional? Does the manga reveal anything about this?
TL;DR: It is possible, though the manga is never conclusive about that.

@senshin I think Migi is able to tell one parasite from another, at least that is the case for a certain parasite. The proof is given on Page 194 in Volume 9 of the manga:


   


So if Kana can reach the level of Migi in detecting and differentiating the signals emitted by the parasites, then she would probably be able to tell Shinichi and Migi from the other parasites. Kana demonstrated her potential with her incredible sensing ability on Page 75 in Volume 5 of the manga:


   


And on Pages 115 and 120 in Volume 5 of the manga, we saw that her powers have evolved.


   


Then there is her dream, in which Shinichi is clearly distinguishable from the other parasites. Conclusion: it does seem promising that Kana might eventually be able to tell Shinichi and Migi from the other parasites had she not rushed to her death at the hands of a parasite when her powers were still immature.