I'm currently running 8.1 on a laptop i bought and got the free update notification. If i install the RTM today that was released, will i lose my free update?
You can't activate a new install since MS has taken down the activation servers for Windows 10 -- and will not be bringing them back up until after the official release on the 29th. You would do best waiting for that instead of forcing an update at this time.
You have more questions, you should really visit the Windows 10 forums: Windows 10 Forums