Have you asked the client? I presume you didn't do 9 revisions for fun, it was because the client asked for changes after each one? So, if the client hasn't asked for changes after the 9th, maybe it's been approved? If it's a fixed price job, you should request milestone approval, just once, if you haven't already. Then it will be automatically approved in 14 days, unless the client approves it earlier, or denies approval. Don't request approval more than once, unless you're submitting another revision. because automatic approval happens 14 days after you request approval.
I already submitted for approval 10 hours ago. I've also asked the client for an update - he isn't responding (even though I see that he is online). See attached image...does this mean he disapproved the work so that he doesn't have to pay?
The client has 14 days (!!) (not 10 hours (!!) to either approve a milestone or request changes.
If the client does not request changes, the milestone is automatically approved.