You say this came from a batch of OG kush but is growing differently, chances are its a different phenotype of that same strain. In some cases you can plant 8 seeds of the same strain and come out with 8 drastically different plants. The strain i am currently growing (nicked sprucezeus) has several unique phenos, One grows very squat and bushy, one is alot leggier, one smells strong and fruity, another pine-ey and subtle. in some cases certain phenotypes are very saught after. Original Cheese, for example, is not its own strain, but actually a stinky, high yeilding phenotype of skunk #1 that has been passed around in clone form for years. Anyhow i hope you now have a better idea of what you're dealing with. Good luck and happy growing.