I created an invoice and saved it, (I did not send it) I want it to be reviewed before I send it. Is there a way I can see only my saved unsent invoices?

Welcome to the Community, Marissa.

Once your invoice is saved in your QuickBooks Online (QBO) account, it will be directly added to the invoice page transactions on the Sales page. Let me navigate you to the site page. 

1. On the left panel of your QBO account home page, select Sales and then choose Invoices. 
2. Look for the invoice you'd like to review before sending it to your customer.
3. When found, click the dropdown button beside Receive Payment, then choose View/Edit. 
   
   
   
   
4. You can then review the invoice you've made. Once done, you can either Save and new or the other provided options beside it. 

In addition, QBO has tools that can customize one's invoice and other sales forms by adding some modifications in the leeway of our business needs. You can check this article to know more about personalizing your invoice: Customize invoices, estimates, and sales receipts in QuickBooks Online.

Don't hesitate to return to this thread if you need further guidance in locating your invoice in QBO. I'll be here to help you out at any time, Marissa. Keep safe!