Indicas will grow quite skinny leaves in the right conditions.. technically hemp is sativa as sativa is a term for utility in terminology. Indica is associated with drug cultivars which largely hail from India.
That said.. yeah, it looks real sativa dominant in the classic head vs body high sense. But even classic indicas can grow very skinny leaves in the right conditions and vice versa (sativa growing thicker leaves). The plant has a lot of ability to adapt to conditions.
It wouldn't be surprising if there were some classic indica genetics in the plant, but really where did the seed come from? Seeded bud? I see by your name you likely are in SE Asia.
I know that there was definitely a lot of genetic pollution of some of the lines in the region in an effort to lower flowering times by commercial producers. But from what I understand there is also plenty of pure still kicking around in corners of the world.