I'm Miles from the Social Care team at Shopify.
At the moment, Shopify's built-in shipping settings don't support per item shipping prices, meaning you wouldn't be able to charge shipping per item using the shipping settings in Shopify.
What I can suggest to you, is the use of some pretty cool apps from our Shopify App Store. I've suggested some of these apps below:
If these aren't suitable, you can find a list of shipping related apps right here: http://bit.ly/2S8o4BU.
Sounds like you're in the testing phase of your store, and trying to get everything just right. I'd love to talk to you a bit more about your store. Have you already got a customer following for your products? If so, have you thought about your marketing and traffic? What kind of marketing activities are you doing at the moment? When you're marketing, think about who you want your customers to be! Think about:
Also, utilize the massive market provided by Facebook and Instagram. Build yourself a loyal following using those platforms. It's more than just spending money to market to people, but more about spending the money to market to the right people, who will be repeat customers and speak well of your business.
We're always here to help, so if you have any questions at all, feel free to reply to this post.