When I press the home key my iPhone 8 vibrates

Ok, understood. At this point, I would suggest trying the following:

(Note: Stop at any step that resolves this. Also note that steps 3 will completely erase your phone and only should be attempted if the first two steps do not help.)

1. Force restart the phone. Ref: Force restart iPhone - Apple Support
2. Perform a "Reset All Settings" reset: Settings > General > Reset > Reset All Settings
3. Restore your iPhone to its factory default settings: Settings > General > Reset > Erase All Content and Settings (Note: The following will erase all of your data and media and resets all of the phone's settings. You will need to restore it from a previous backup from either iTunes or iCloud.) Ref: Restore your iPhone, iPad, or iPod to factory settings - Apple Support

No need to be sorry. If anything, I'm sorry that none of that helped. It does look like your next step would be to make a Genius Bar appointment at your local Apple Store or with an Apple Authorized Service Provider to have them take a look and provide you with your options.

As far as restoring from a backup, it will depend on where that backup is located. Regardless, the following support article should prove helpful to answer that question:

• Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Then, with it off, your phone should not provide any mechanical feedback, and since it still does, may mean something is amiss with your phone. What have you tried, so far yourself, to resolve this? For example: restarted the phone, "force" restart the phone, perform any of the phone resets, or completely restoring it to its factory defaults?

Do you have haptic touch enabled on this phone? If so, that could be the reason.

Ref: Change 3D or Haptic Touch sensitivity on your iPhone - Apple Support

I mean, that sounds more like the screws were loose. The threads don’t break from a drop...