It sounds like your the sleep button itself is waking your computer. One thing you could try is disabling the sleep button's ability to wake your computer. You can do this in the power configuration.
Control Panel (All Items) > Power Options > Change Plan Settings > Change Advanced Power Settings > Power Buttons and Lid
Change the action of the Sleep button from "Sleep" to "Do Nothing"
This behavior might also go away if your update/install the correct drivers
for your notebook. I'm not certain which of the various sets of drivers you'll need, but you should be able to find them on your manufacturer's website.