Being petite can sometimes be challenging. The best way to avoid looking "tiny" is by wearing a higher heel like a platform or wedges. This will give you more height and make you look taller. As for wearing a top to look more fashionable, you may consider a longer t shirt paired up with a blazer/or jacket.
This will also give the illusion of being taller. Your jeans sound classic so by adding a trend like an updated T shirt with current jewelry will give it a fresher look as well. Don't be afraid to try new things, you will be pleasantly surprised.