the idea that
weight lifting will stunt your growth is a myth. there has been no evidence to back up the theory that regular weight-training causes any damage to the growth caps on the ends of the long bones. there have been cases where teens have lifted HEAVY - i mean way heavier than you'll manage any time soon - and with bad form causing injuries that did affect growth, but these are few and far between.
use common sense, observe good form, eat a
clean diet, get lots of sleep, don't work the same body part any sooner than three days later, and you'll do just fine.