I believe you would be paid in september. The 5th for EFT, and the 25th for checks(if you don't get paid by those dates you can request a reissue). Look in the payment history section of you adsense report, right below "todays earnings." Congratulations on your first $100...I'm still working on achieving that goal myself.
We can't do anything about it. It's their rule of paying their publisher. If you are earning cross $100 every month then you will not have any issue because you will be getting Cheque every month.
Go check your Payment History. If it shows Payment In Progress or Payment Issued, you are most likely to receive the payment August.