Atarantado is a colloquial and expressive word that means 'dazed', 'bewildered', or 'smitten'. It's not a word you hear every day, making it quite memorable.
In the song, the singer says, "Chiquitita, me traes bien atarantado" (Little one, you have me completely dazed/smitten). He uses this word to convey how overwhelmed and captivated he is by his love interest, to the point of feeling a bit disoriented by his strong feelings. It perfectly captures the feeling of being head-over-heels in love.
Ulices Chaidez's "Chiquitita" is a sweet and direct serenade from a guy who is completely smitten! He tells his "Chiquitita" (little one) how much he likes her and how badly he wants her to be his. He's so in love that he thinks about her constantly, saying, "Cada noche antes de dormir yo te pienso Y cuando despierto sigues en mi mente" [Every night before I sleep I think of you And when I wake up you're still on my mind].
He's so head-over-heels that he feels "bien atarantado" [really dazed or flustered] by her. He promises to write "mil canciones de amor" [a thousand love songs] just for her, hoping they'll help him deserve her "labios rojos que saben a miel" [red lips that taste like honey]. It's clear he's already picturing their future together, declaring, "Ya me vi siendo de usted" [I already see myself being yours]. It's a charming and earnest declaration of love!