Submitted the wrong proposal

[#1]

So I received an invitation for a job and I currently do not have any connects. I decided to try sending one with placeholder texts just to confirm that Upwork indeed takes connects for jobs you're invited to. To my surprise it does go through and I just submit a bunch of nonsense texts to my client. 

I know it was a foolish thing to do, but I was certain it wouldn't go through as I had zero connects. 

What can I do now?

[#2]

Withdraw your proposal and leave your information in the message.

If the client wants to interact, they will.

[#3]

Yes, withdraw your proposal since it's pure nonsense.