Load testing a Google App Engine Application using JMeter

I've created an application and I'd like to test how well it scales to large numbers of users.

To run my application a user has to go to the homepage, sign in to a Google account, click a button and then upload a video file.

First of all, is this possible to emulate using JMeter? I'm signed into my Google account locally but am not sure whether simulated users will have access to it?

Secondly, I've recorded a session in JMeter doing the actions above and have run the test with 10 simulated users, however, the App Engine dashboard doesn't detect any activity. I've followed the steps mentioned here but obviously with details of my application etc.

Here's a screenshot of the summary report.

Is there anything obvious I might be doing wrong? Am I using JMeter in the correct way to test the application as desired?

Apologies for my JMeter inexperience.