Hi Sara! I hate to hear that you're frustrated, so let's see if we can get this squared away.
Can you let me know the name of the mailing you're working on, since there are quite a few that were recently modified. I will say that if you're working on a Code your own HTML mailing, the test groups in your account do not carry over to the "Send Test" panel for any Code your own HTML mailings. This means that you'll just have to type in or paste up to 10 email addresses in that recipients section.
I will keep an eye out for any additional information you might provide here!