How Chrome handles new pages/tabs in phones varies.
My iPhone 6+, each new tab has to be closed manually, but can be accessed from the Chrome for iOS tab menu.
On my Galaxy s5, hitting "back" closes the tab and reverts to the last one that was open or that launched that new page/tab.
If I want to select among the tabs or close them out manually however, there is no longer a tab menu, they only all show up as active tasks in the stack from the s5 menu/tasks button, and I have to X-them out, or flick them away from there.
So how Chrome handles tabs is really a mix of Chrome, the phone OS, and even in Android, a mix of Chrome and the particular phone/flavor of Android it's running and what soft-buttons or perma-buttons your phone has on it's face.
Honestly, any Android you've been using for more than a year probably would benefit from a backup, wipe, and factory-reset from the bootloader/recovery menu. (Usually some combination of the power, home, and one of the volume keys when powering up) Then (re)running all updates offered by your carrier, and bringing down all your apps from the Google Play Store again.
If that seems too drastic, try wiping the cache partition from the bootloader/recovery menu at least.
