No. Not really. I think a translation for "freak" would be most befitting of the tone of the song.
any abnormal phenomenon or product or unusual object; anomaly; aberration.
a person or animal on exhibition as an example of a strange deviation from nature; monster.
The song is about a guy who feels inferior to a girl because of his looks, tastes, desires. He refers to her as an angel and implies that he is far from an angel, that he doesn't deserve her. "What the hell am I doing here?" He feels like an aberration around her and in her world.
Perhaps we could assume that he is hideous as he contrasts with her, who is angelic, but it's a leap to use the word disgusting. He is simply an outsider in her world, and feels beneath her.
Etymonline, gives a few possible origins for freak, including:
1560s, "sudden turn of mind," of unknown origin, perhaps related to
O.E. frician "to dance" (not recorded in Middle English, but the word
may have survived in dialect) [OED, Barnhart], or perhaps from M.E.
frek "bold, quickly," from O.E. frec "greedy, gluttonous" (cf. Ger.
frech "bold, impudent"). Sense of "capricious notion" (1560s) and
"unusual thing, fancy" (1784) preceded that of "strange or abnormal
individual" (first in freak of nature, 1847; cf. L. lusus naturæ, used
in English from 1660s). The sense in health freak, ecology freak, etc.
is attested from 1908 (originally Kodak freak, a camera buff). Freak
show attested from 1887. The verb meaning "change, distort" goes back
to 1911. Earlier, "to streak or fleck randomly" (1630s).
The Middle English "frek" and German "frech" seem closest in meaning to the English, but my skills do not suffice to tie that to anything Portuguese.
Google Translate provides "aberração" as the top translation of freak, but that, I'm guessing, is closer to "aberration." "Aborto" looks like it has the meaning of "monster", which could work.
For what it's worth, I have Portuguese-speaking friends who use the English word. Spanish and Catalan people do as well, although in Spanish a "friki" is more of a "nerd" than a "freak".