You can upload image(s) and press Generate multiple times as long as you have the credits for it.
Keep in mind, that if you submit 10 different objects for generation quickly one after the other, your objects will be processed sequentially i.e. one after the other, not in parallel.
We encourage you to do this as then you won't be needing to come back to the app every 10 minutes to submit the next one and you can be looking at your Asset Library for the finished models.